# OK - I give up - I fail at tanks and need help



## gaimrox (Dec 2, 2011)

Hi,

Little background - I've had planted tanks since 2001. I've got a lot of experience with basically all aspects of the hobby - but it has all failed me and my tank currently looks *awful*.

I am attaching pics here. I will also be attaching whatever water measurements that people might need to help me diagnose this - although note that there are no giant red flags of "your xyz is way too high".

The tank has looked awful for 2 years. I tore the tank down a year ago to move, but ended up reusing most of the materials. Unsurprisingly the problem returned.

I tore the tank down 6 months ago, bleached components, got a new light fixture, 99% water change, new substrate, etc. Tank looked awesome, but it has now returned to the state you see before you.

I have a few clown loaches in here that I've had for years, they love eating nerites. So basically I am now feeding them nerites, as nerites sort of seem to help control the problem - but obviously there is way too much growth for them to control it outright.

ALL SUGGESTIONS WILL BE CONSIDERED. Clearly I don't know what I'm doing.

Tank is a 75 gallon, gets 50% water changes with RODI water about once a month. 220 watts that run 4 hours, cut for 4 hours, run another 4 hours. Has c02. PH runs at 6.4. There is eco complete on the bottom of the tank. The light fixture has brand new bulbs. 

The tank tests for nitrates/nitrates/phosphates all right near zero. I am not currently dosing ferts, but I have in the past, not much changed when I did.


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## gaimrox (Dec 2, 2011)

Ugh those pictures look so bad - thanks in advance. I've lurked on this board for a long time but could never admit that the problem was beyond me.


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## OverStocked (May 26, 2007)

220 watts of what kind of light? Is it actually like 216 watts of t5HO? If so... OMG, that is A LOT OF LIGHT! 

You HAVE to dose ferts. With this light and co2 level, you're only hurting things. Lots of options out there, from dry ferts with PPS Pro and EI, to liquid ferts like my product(RootMedic) or pFertz. 

Seriously, that is a TON of lights. 

Algae has a simple equation: too MUCH light, too LITTLE co2, too LITTLE ferts. I'd say you have at minimum hit too much light and too little ferts. LIkely with THAT much light, you have too little co2 as well. 

When we put our lights in critical high levels, you have to constantly chase the light with ferts and co2.


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## tetranewbie (Oct 6, 2010)

What kind of lighting is it? Watts mean different things with different types of light... T5, PC, LEDS? And with that much light and CO2, you'll need fertz. 

Also - I think I see a drop checker, what color does it run?


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## JasonG75 (Mar 1, 2011)

And Why use RODI?


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## OverStocked (May 26, 2007)

JasonG75 said:


> And Why use RODI?


Lots of reasons to use RO. All I use is RO now. My tap water comes out at a pH near 9.


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## gaimrox (Dec 2, 2011)

It is t5HO. I saw a spectrum analysis of the bulbs - they are decent, but not the best. They are from China.

Also I have a glass lid on the tank that reflects a good bit of the light.

I previously had a 220 watt CFL square pin light on top, and swapping to this fixture made such a huge difference almost overnight that I was convinced the old light sucked compared to the new one.

I am getting an acrylic tank lid. I have a bunch of SAE in there, big ones, and they jump far! They need to be contained.

Very little evap in the tank.

As noted the lights are on for 8 hours a day, so I dont have a crazy light schedule like other people do.

The fixture either has all 4 T5 on, or all 4 off. No in between option unfortunately.

Lights come on at 8am, turn off at 12, turn on again at 4. The tank is sort of near a window, but it doesn't appear that too much light comes in that way.


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## gaimrox (Dec 2, 2011)

I use RO water because I live in Washington DC and the water here is foul. I do not do a great job of remineralizing it however. I tried reminining it for a while, noted it didn't help, and stopped.

I still have remin stuff here to restart that process if that is the cause.

I one time gave up on the RO, and used right from the tap water. I prefer right from the tap, it's easier.

I added the chloramine/chorine nuetralizer. Added it to my tank. Then I had a few fish die instantly right in front of me. I... am pretty sure that meant the water was tainted. I do not drink it anymore


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## gaimrox (Dec 2, 2011)

The drop checker is there, it is green. I tore the oring on it and am looking for a replacement right now. It has been bright green for about a year. The CO2 looks functioning and keeping levels at a decent amount.

There is a PH checker hooked up directly to my CO2 valve that controls how much CO2 comes out, I should have mentioned that.


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## tetranewbie (Oct 6, 2010)

A glass or acrylic lid helps cut down on the light, but you still have WAY too much for what you're currently doing with the tank...

How's your CO2 level?
Have you tried taking two bulbs out of the fixture? 
And if you don't want to cut down on your light, you'll probably need to up the CO2 and start fertilizing big time.


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## OverStocked (May 26, 2007)

You need to run less light. I seriously can't emphasize this enough. No ifs ands or buts about it. Unless your hood reflects 90% of the light, it doesn't matter. 

Can you pull a bulb or two out and see how that works? It should still run without them. 

TOO MUCH LIGHT. 

On my 75 gallon tank I run 2 t5ho bulbs and they are about 11 inches from the surface of the tank. No co2, but only 7 hours total. 4 t5ho bulbs on the tank top produce soooo much light it isn't even funny. If you're not dosing ferts, you'll never be successful with this combination. Even with the ferts, that much light means you will be constantly chasing it. 

Find a way to reduce light. Raise the lights. Run half the bulbs. Put window screen in there. Something. 
_
Insanity: doing the same thing over and over again and expecting different results.
Albert Einstein_


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## tetranewbie (Oct 6, 2010)

Also- if you're no longer remineralizing your RO, you have VERY soft water... that means that the pH will drop very quickly with the addition of your CO2, and you won't actually be getting that much into the water.


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## gaimrox (Dec 2, 2011)

I should mention that I have tried root tabs as well. Root tabs were awesome because it prevented the holes in the leaves from forming. Leaves sometimes grow really fast and have holes - so that seemed obviously to be a chemical deficiency.

In addition I have bags and bags of Rex Griggs ferts over here of basically all kinds. It's not immediately clear to me which I would add or why however, so I have largely avoided dosing the water column directly.

I have mostly stuck with ferts from the store in those bottles with careful directions.

Note that when I add ferts plants do grow faster, but the algae is totally out of controls and grows even faster, ultimately leading to covering of the leaves.

The tank as you see it is actually "decent" since the plants didn't turn black and die like last time...


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## OverStocked (May 26, 2007)

tetranewbie said:


> Also- if you're no longer remineralizing your RO, you have VERY soft water... that means that the pH will drop very quickly with the addition of your CO2, and you won't actually be getting that much into the water.


The co2 carrying capacity of water is almost uneffected by the hardness or pH of water. Having soft water does not mean there will be less co2 in the water. Not for our purposes anyways. 

Co2 related pH changes are basically irrelevant.


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## OverStocked (May 26, 2007)

gaimrox said:


> I should mention that I have tried root tabs as well. Root tabs were awesome because it prevented the holes in the leaves from forming. Leaves sometimes grow really fast and have holes - so that seemed obviously to be a chemical deficiency.
> 
> In addition I have bags and bags of Rex Griggs ferts over here of basically all kinds. It's not immediately clear to me which I would add or why however, so I have largely avoided dosing the water column directly.
> 
> ...


*too. much. light. *


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## gaimrox (Dec 2, 2011)

Ah another element with regard to remineralizing.

I had co2 problems because I had water that had no buffering capacity. For a while I added baking soda, but that was annoying, so I threw a couple texas holey rock in there.

That combined with water changes seemingly got my GH/KH in better shape. I have pulled those rocks as of last week.

Additionally I have a turbotwist sterilizer, but that is currently unplugged as of last week as well.


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## gaimrox (Dec 2, 2011)

Popping out 2 bulbs is a good idea, I imagine it would still work and probably save me some dollars.

That seems like a good starting point.


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## gaimrox (Dec 2, 2011)

Ok while there was only 1 switch, there are actually 2 plugs. So I unplugged one pair.

Question - is this a single variable fix? How long to wait before seeing any kind of change?

I don't expect there to be overnight magic or whatever, but in a month would we expect to see less algae on the leaves for example?


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## gaimrox (Dec 2, 2011)

Also should I still turn off the lights on a schedule, or would I stick to have 110 watts of light on for 12 hours in a row?


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## OverStocked (May 26, 2007)

Well most algae won't just go away. Manually remove it, research dosing with peroxide or excel, and do some water changes. THe goal here would be less algae in the future. 

You still need to find a good dosing solution. The dry ferts you have are easy enough, if you look into EI dosing as a start. 

If you want a liquid solution, stop using the seachem/etc. Either look at pfertz, or my line from www.rootmedic.net. Concentrations and content are actually useful.

I would run your lights 8-10 hours.


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## Fishball7 (Dec 2, 2010)

+1 what overstocked said.

Excuse my limited plant id knowledge. The plants you have seem to be low light ones, which can't process that much light fast enough with those amount of fert and co2; if they are high light plants then theres not enough ferts and/or co2, so algae out competed them and took over the tank. 

You'll have to scrub the tank and do a good water change. Add some right types of algae eaters would help with the ones you can't get to. Consider not turning on the lights for a couple of days to help kill off the algae.


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## thefisherman (Oct 15, 2011)

http://aquariumalgae.blogspot.com/

this site has helped me understand algae basics


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## tetra73 (Aug 2, 2011)

Your tank happened to be this way because you have too much light. No ferts. Not sure about your CO2 level. Try to place the drop checker at the far side from your CO2 diffuser. It does not matter how much CO2 is coming out near your diffuser. It is whether the far corner of the tank has even CO2 level. 

Cut down your light and keeping it 8 hours lighting period top.

Use EI dosing + root tabs. You appear to have some sort of crypts. They can do fine under medium to low light.

Keep your CO2 level in the lime green to yellow. 

To reduce your light intensity, you can elevate your light fixture higher. Or placing a fiberglass cloth by the bulb cover.


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## kevmo911 (Sep 24, 2010)

The last few posts didn't answer your last question, so I'll try: weeks. Honestly, you can follow through with any or all of the suggestions - they're all good - but it will take awhile before you realize it. Either lower light, or increased CO2 and ferts, or both. You said that nobody would find an obvious problem, but we all did, so follow through with the suggestions or not. If you get rid of as much algae as you can, and wait a few weeks, you'll see a difference. Take a picture before and after and you'll definitely see it, but don't expect results in a matter of days. It takes real time.

Light drives the demand for CO2 and nutrients. Lower light, lower demand. Higher light, higher demand. Imbalance = poor growth and algae.

I have 6 tanks, and my most beautiful tank, the tank I love to watch, is a 25g with 30w of T8 with a crappy DIY reflector (white aluminum flashing) and pressurized CO2 (although it was just as beautiful a couple months ago with the same lighting and ferts, low EI, no CO2), though not quite as lush. You're overdoing it.

If you aim for high light, even with CO2 and heavy ferts, you will absolutely, positively, "I bet my next paycheck on it (seriously)" have algae problems. It's a balancing act. To get a high-light, algae-free, beautiful tank (even with CO2 and ferts), it will take a lot of work, and a lot of maintenance. Ask any of the powersellers how long it took before they started making money from this hobby. Most of them still don't. Start low, and work up.


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## gaimrox (Dec 2, 2011)

There are quite a few crypts in here. It's the only plant that seemingly could survive in this environment.

During a more successful part of the tanks life there were 4 separate lilly plants, and about 8-9 swords, along with glosso and riccia. All of that seemingly was outcompeted by the algae. There was a very brief time where the tank looked decent, where it was lush with plants, but then the algae pretty much wiped it all out.

The lillies are actually still in there, but they cannot actually make a leave without it being covered.

It takes about a single day from when a new leaf grows before it gets a brown algae covering on it.

Additionally there have been some periods of time where I have left on vacation, and a friend has suggested I do "lights out" for a few days (as also suggested on this thread) in order to try and combat the problem... upon return it appeared that the algae growth had seemingly accelerated, while some of the plants had gotten weaker. So I am hesitant to do a lights out again.

I have before and after pictures from most of my attempts, but I have never tried turning off 2 bulbs before. I always did on/off type stuff - so we'll see how that pans out.

I did recently put a round of root tabs in, although I'm not quite sure how long those last.

Additionally an AZ gardens order came with a [censored][censored][censored][censored] ton of snails and a couple SAE - so maybe those will help. I ordered a few swords along with some other random plants, so we'll see how it goes once the plant biomass is increased.


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## gaimrox (Dec 2, 2011)

I have a large CO2 diffuser made from PVC under the tank. I'm sure you are all familiar with the design of them.

That is then fed by an eheim cannister filter. The output of the filter is in the middle of the tank, so the CO2 meter is as far away from that as it actually could be.


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## Naekuh (Oct 19, 2011)

kevmo911 said:


> If you aim for high light, even with CO2 and heavy ferts, you will absolutely, positively, "I bet my next paycheck on it (seriously)" have algae problems. It's a balancing act. To get a high-light, algae-free, beautiful tank (even with CO2 and ferts), it will take a lot of work, and a lot of maintenance.


we newbies cant understand that notion fully until we get caught in it. :bounce:

lastly never get livestock to fix your algae... i learned this the hard way too, your shifting one set of problems onto another, and not fixing it.


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## livingword26 (Oct 28, 2010)

OverStocked said:


> The co2 carrying capacity of water is almost uneffected by the hardness or pH of water. Having soft water does not mean there will be less co2 in the water. Not for our purposes anyways.
> 
> Co2 related pH changes are basically irrelevant.


Except that he is using a ph controller.


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## livingword26 (Oct 28, 2010)

2 bulbs only on the lights. You have to reconstitute the rodi water every time to the proper hardness, otherwise your ph controller will be unreliable if you have no gh, and the plants aren't getting all the minerals they need. You still have high to medium light even with 2 bulbs, you are going to have to dose ferts. You need:

10 - 20 ppm Nitrates
10 - 20 ppm Potassium
1 - 2 ppm Phosphates

and of course a micronutrent mixture.


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## OverStocked (May 26, 2007)

livingword26 said:


> Except that he is using a ph controller.


And............... ? Seems you have a few disconnected thoughts here. If a tank actually has a kh/gh of zero then yes, pH would swing wildly. However, unless you have a sterile atmosphere, I highly doubt it to be zero. In combination with a tank that gets too little water changes, the TDS and likely KH are prob high enough to prevent wild swings. Assuming it isn't is a stretch. 

What happens when the KH is low is that the carbonates get burned through by plants and bacteria and then you could get wild pH swings. If the OP was having this happen, the livestock would be dead by now. 

Remineralizing water could be as simple as mixing with tap(I mix 10% tap 90% RO). 


livingword26 said:


> 2 bulbs only on the lights. You have to reconstitute the rodi water every time to the proper hardness, otherwise your ph controller will be unreliable if you have no gh, and the plants aren't getting all the minerals they need. You still have high to medium light even with 2 bulbs, you are going to have to dose ferts. You need:
> 
> 10 - 20 ppm Nitrates
> 10 - 20 ppm Potassium
> ...


pH and GH are unrelated. KH directly ties to pH swings. These targets you estimate seem to possibly be based on EI. Plenty of tanks thrive just fine with lower levels. If you're going to have targets for macros and none for micros, you're missing a bigger picture. 

Lots of ways to dose, not all of them believe you need to have 20 ppm of nitrates. Pulling out specific numbers we HAVE to reach is a good way to scare people away from dosing. 

You can use a pH controller just fine in a tank with low pH/gh/kh. In conjunction with a drop checker you are golden. Not knowing the actual GH/KH/PH means we can't make a bunch of assumptions.


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## livingword26 (Oct 28, 2010)

OverStocked said:


> And............... ? Seems you have a few disconnected thoughts here. If a tank actually has a kh/gh of zero then yes, pH would swing wildly. However, unless you have a sterile atmosphere, I highly doubt it to be zero. In combination with a tank that gets too little water changes, the TDS and likely KH are prob high enough to prevent wild swings. Assuming it isn't is a stretch.


A high light tank needs weekly water changes, and while doing 50% weekly water changes with rodi water won't make the kh/gh 0, it will certainly be low, especially since he is not dosing any ferts. Also the kh/gh doesn't have to be a perfect 0 to produce an unstable ph. So I'm not sure what your point is here. The plants need the minerals, and so does the water for ph stability.



> What happens when the KH is low is that the carbonates get burned through by plants and bacteria and then you could get wild pH swings. If the OP was having this happen, the livestock would be dead by now.
> 
> Remineralizing water could be as simple as mixing with tap(I mix 10% tap 90% RO).
> 
> ...


So it seems you are saying that the op doesn't really need to worry about his npk or mico's? I've given him the range that I use, but you have suggested? If he is scared off by the knowledge that he needs to know what is going on in his tank then he doesn't have much of a chance anyway. 



> You can use a pH controller just fine in a tank with low pH/gh/kh. In conjunction with a drop checker you are golden. Not knowing the actual GH/KH/PH means we can't make a bunch of assumptions.



Agreed that the actual reading is necessary, especially when using rodi water.


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## OverStocked (May 26, 2007)

livingword26 said:


> *A high light tank needs weekly water changes*, and while doing 50% weekly water changes with rodi water won't make the kh/gh 0, it will certainly be low, especially since he is not dosing any ferts. Also the kh/gh doesn't have to be a perfect 0 to produce an unstable ph. So I'm not sure what your point is here. The plants need the minerals, and so does the water for ph stability.


Say Wha? Says WHO? You only *need *to use weekly water changes of 50% if you are dosing EI with a goal of excessive dosing. Lots of assumptions or opinions as fact in your posts. That is my whole point.


> So it seems you are saying that the op doesn't really need to worry about his npk or mico's? I've given him the range that I use, but you have suggested?


I didn't say that. I suggested that the OP needed to be dosing before anyone even read this thread. What I am saying is that those numbers are arbitrary at best and aren't some sort of magical requirement to a happy tank.


> Agreed that the actual reading is necessary, especially when using rodi water.


If the OP uses a DC you'll have a decent idea that the co2 is a reliable number.


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## livingword26 (Oct 28, 2010)

OverStocked said:


> Say Wha? Says WHO? You only *need *to use weekly water changes of 50% if you are dosing EI with a goal of excessive dosing. Lots of assumptions or opinions as fact in your posts. That is my whole point. I didn't say that. I suggested that the OP needed to be dosing before anyone even read this thread. What I am saying is that those numbers are arbitrary at best and aren't some sort of magical requirement to a happy tank.


ar·bi·trar·y   [ahr-bi-trer-ee] Show IPA adjective, noun, plural -trar·ies. 
adjective 
1. 
subject to individual will or judgment without restriction; contingent solely upon one's discretion


Personally i think Arbitrary is a inappropriate adjective. Many people use, and have used these numbers with much success. They are, as you have pointed out rooted in EI dosing, which has much study behind it.



> If the OP uses a DC you'll have a decent idea that the co2 is a reliable number.


Assuming that the drop checker has the appropriate 4dkh solution in it, then you do have some idea what level of co2 is in the tank. But using adjectives like bright green leaves some room for interpretation. I run mine at a yellowish green, and I suspect that I am between 30 and 40 ppm.


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## Naekuh (Oct 19, 2011)

OverStocked said:


> Say Wha? Says WHO? You only *need *to use weekly water changes of 50%


i thought weekly water changes is what was recommended by all the people here.

i stuck to that habit of doing a 50% weekly.. every saturday to be exact.

Are you telling me, that i can hold off my 50% every week?


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## kevmo911 (Sep 24, 2010)

Completely aside from the increasingly irrelevant argument going on here (seriously, guys, cut it out), 50% weekly water changes are only necessary in the case of EI dosing, just to keep the maximum excess nutrients at a fixed peak.

That said, 50% weekly water changes are never a bad thing unless they're undermining your attempts to keep parameters at a fixed point.


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## narhay (Feb 28, 2007)

2 bulbs, dose dry fertilizers (nitrate, potassium, phosphorous, trace elements) regularly and keep your CO2 going. Some people don't see the immediate success of dosing fertilizers and quit after a couple weeks. This is a bad idea. You've been keeping aquariums for awhile so you could get this under control no problemo.


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## gaimrox (Dec 2, 2011)

Yeah I'm running the 2 bulbs. I scored around 15 nerite snails who have been chunking along slowly cleaning off some leaves. The little nerites actually do a pretty decent job - I usually got tiger nerites, but these are far better at the task.

The only notable thing to report right now is the appearance of tufts of BBA around the tank. I have not had any BBA in there for well over a year, so that's a little disconcerting - staying the course to see what happens.


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## gaimrox (Dec 2, 2011)

Also as for nitrate/nitrate, phosphates - the last test I did measured these at zero or close to zero. There are no free floating materials in there.

What's going to be the better scenario. Dosing to get these up to the recommended level, or holding them at zero?


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## tbarabash (May 18, 2011)

Dosing them to get up. 100%.

I never used to dose proper EI in my tank, I would put flourish comprehensive in 3-4x a week and my nitrates would still be 0 cause my plant load was too much, growth was stunted, things just didn't look right. I set up a new tank, (high light like yours, 158W t5ho over a 36 bowfront(yep, that's right. 3 fixtures haha..trying to get *all* my fuggin stems to be nice and red) and tried to stick with crappy premixed ferts and my GSA and BBA took off. I switched to dry EI dosing, found a good CO2 bps that would juuuuuust get some of my fish hanging around the top of the tank before lights/co2 off, and am religious with my 50% water changes every weekend and my tank is thriving like I never imagined it could have, almost algae free. It's been about 2 months now, sometimes I get a couple (literally just a couple) small GSA dots here or there when my po4 are low, orI get a small tuft of BBA here or there when my filter output slows down and isn't circulating co2/water properly enough but it gets munched on by my SAE and doesn't come back once I fix the circulation problem. 

But until you're at the point where you can look at your clean tank and start fresh again definitely stick with the 2 bulbs, remove as much algae as you can, bomb your tank with excel or peroxide to give yourself a head start and start dosing dry ferts (oh so cheap compared to others). Good luck >.<


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## csmith (Apr 22, 2010)

I'm amazed you've endured a decade of this. I'd have definately thrown in the towel by now. Kudos for that. As has been said before, but probably should be repeated:

1.) Definately cut down on the lighting. Lighting drives the need for CO2 and ferts. Less light, less of everything else that's needed.

2.) Definately dose ferts. You never want your ferts at 0, the plants need them to grow. If the plants don't have what they need to grow, the algae is all too happy to do the growing. This is Estimative Index dosing. As you have the ferts in hand already, it costs you nothing but the effort you need to make.

3.) Do not rely on a green drop checker.

4.) Do not rely on a green drop checker.

..and most importantly..

5.) Do not rely on a green drop checker. Turn the CO2 up (*slowly, over a good span of time*) until basically the fish can't handle it, then back it off a little. Then your CO2 is good. I've run lemon yellow DC's in both of my tanks since I've had them. Drop checkers are in no way an infallible item.

There is no easier way to get where you want to be than doing this. None.


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## gaimrox (Dec 2, 2011)

To the last poster - I had very good luck with tanks during most of my time with planted tanks. That said, this current setup had been very challenging (not the word "had" - I solved it).

I'm back, many months later. I'm following up so that others who may have a similar problem will hopefully be able to solve their problem.

To recap: I read all of the advice above, the most frequent suggestion was using just 2 bulbs.

I tried this. 4 weeks later the tank was completely overrun by the creeping algae. So that suggestion - sometimes accompanied by deprecating comments - was not a good one.

I purchased new bulbs - waited another couple weeks, and the same progression was occurring. This eliminated that bulb age was a factor.

I then returned back to water column dosing, something that in the past I had found was completely unnecessary for the kinds of plants that I was growing. No luck either unfortunately.

Copious amounts of water testing showed that the tank water was compliant, i.e. the RO water was in fact RO water. I decided at that point to stop using RO water. No change after doing that for about 3 months (took a while for me to 30% water change it all out).

Tap water here is rather high in phosphates, so I played a few games with dosing ferts around that. Another 4 weeks later, no change.

At this point I basically had a bunch of stumps. The plants would grow new leaves, but the leaves would become covered in less than a week and die.

Finally randomly I noticed a little clump of BGA, which I have very successfully dealt with in the past by using Erithromycin.... AND BREAKTHROUGH.

3 weeks after this event all leaves are completely green. My dwarf lillies are going nuts. There is pearling on some of the leaves of other plants. It's completely nuts.

It's not clear to me whatever was covering the leaves, but whatever it was responded very strongly to erithromycin, and things are all good on my end. I can post new pics if anyone wants to see.


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## rrastro (Jun 14, 2012)

I'm glad it worked out for you in the end. FWIW are you still on 2 bulbs or back to 4?


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## gaimrox (Dec 2, 2011)

I had always run the fixture with the 4 on prior to the suggestion of only going with 2.

Once I tried the 2 I can't say I noticed any less or any more growth than with the 4. Prior to the erithromycin it made no observable difference, although people commented the tank looked substantially worse - I think that was because it looked darker though, not because the rate of "algae" coverage had accelerated. It basically looked equally as terrible to me.

Another thing I tried was dramatically cutting light for about a week. The tank was in a basement and did receive some indirect light from a basement window - but other than that it received very little (maybe from a nearby 60 watt bulb that was a few feet overhead - again, indirect light). During this period the plants got completely covered - whereas normally they would produce a little leaf or two that would be clean.

I'm not sure the "algae" was ever light dependent. It's a pretty strange thing really. I have a number of snails that will eat it, but it grows so quickly that they couldn't put a dent in it. It's not slimy to the touch, it more feels like it's part of the leaf. It could not be rubbed off, even with a toothbrush... but you could visibly see that it was a layer on top of the leaf itself. Also it never grew on the glass - *except* for the back glass. The back glass is painted black on the outside, and that glass did get covered. So weird.

In any case right now I go back and forth between the 4 and the 2. The tank looks nicer with the 4, and I'll get visible signs of photosynthesis with the 4, along with almost neon green leaves... but I do the 2 also to save on some power. Depends on what I'm feeling that day really.


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