# considering low tech, need advice



## Oqsy (Jul 3, 2004)

by rex's minimum light threshold, i need about 4320 lumens to qualify as "low" light for this tank. that sure sounds like a lot of lumens... i wonder how many I already have. i can't seem to find lumens ratings for any of my bulbs online... most/all of them on this tank are zoo meds... ocean sun 10000k, and the ultra sun 6500k. zoo med site doesn't even list lumes... anyone with specs?

Oqsy


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## Rex Grigg (Dec 10, 2002)

I have a 20 High with a single AH Supply 55 watt kit over it. That's 2.75 wpg and as I recall right around 4400 lumens with the current bulb. It not quite a low light tank but just a hair above being one IMHO.


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## aquaverde (Apr 15, 2003)

The basic thing that drives EI is CO2 enrichment, not high light. If you want to stop dosing, pull the CO2 off the tank as well. With the plants you have, I think you don’t need CO2 anyway.

If it were my tank, I would cut the light to around 2.5wpg or a little less, and replace the stems with crypts.


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## Oqsy (Jul 3, 2004)

but if the plants are nitrogen, phosphorus, or potassium limited, would the co2 do any damage? is it not beneficial to lower light tanks, as I have read? don't get me wrong, I don't *want* to waste CO2, I'm just curious... thanks

Oqsy


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## aquaverde (Apr 15, 2003)

Oqsy said:


> but if the plants are nitrogen, phosphorus, or potassium limited, would the co2 do any damage?
> 
> Oqsy


No more than if the light remains high. Actually, somewhat less. 

Put it this way. Those exact conditions resulted in an algae mess for me at 2.25wpg. After I pulled the CO2, the algae cleared up. That's not scientific method, just my observation, so ymmv. But Barr states dosing goes with CO2, even for lower light levels.


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## ceg4048 (Mar 26, 2004)

aquaverde said:


> The basic thing that drives EI is CO2 enrichment, not high light. If you want to stop dosing, pull the CO2 off the tank as well. With the plants you have, I think you don’t need CO2 anyway.


Sorry, but I disagree with this statement. EI is based fundamentally on the concept of nutrient deficiency avoidance by dosing to slight excess, which includes CO2. Inappropriate limiting CO2 is just as damaging as inappropriate limiting of NO3. The actual driver is light. If you look at the parameters of the baseline EI 20 gallon tank you'll see that the illumination is 5.5wpg. I'm unsure exactly how Tom Barr arrived at this value. It could be that he considered that this would be the top end for most tank owners or, I suspect that it's more likely that his studies indicated that more light beyond this value does not significantly increase nutrient uptake.

Based on this maximum light level driving the maximum nutrient uptake the dosing levels guarantee that there will not be any dificiency. The NO3, PO4, micro and CO2 target levels in the dosing scheme are based on this maximum uptake level all driven by the maximum light.

The "low tech" (Non CO2) method was developed for those tired of living on the edge with constant dosing and pruning. The rule of thumb threshold level for being considered "low tech" is once again the light level. From 1wpg to 2wpg and with the deletion of gas injection, CO2 then becomes limiting and growth slows.

You needn't live on the extremes however. No one says that you can't have a "medium tech". As long as you stay below the 2wpg (more or less) to avoid engine revving, you can still inject C02 or add Excel and acheive 2 to 6 times more growth as compared to non carbon supplementation.



aquaverde said:


> After I pulled the CO2, the algae cleared up. That's not scientific method, just my observation



I'm hard pressed to belive that there is any correlation between CO2 deletion and algae removal. CO2 level increase is one of the main factors that trigger algae dormancy, so something else must have changed along with the loss of CO2. You can't draw this conclusion unless you can verify that all other variables remained constant and that only the CO2 changed.



aquaverde said:


> If it were my tank, I would cut the light to around 2.5wpg or a little less, and replace the stems with crypts.


Huh??? Stems do just as well as other crypts in low tech. They just don't grow as fast as stems in a high tech environment. Hygros, for example can dominate any setup if you allow them to. Of course that's assuming you dose the water column. If you don't dose, then yes, root feeders will have an advantage. You still dose with a low tech, you just don't have to dose nearly as often as with high powered laser beam setups.



Oqsy said:


> but if the plants are nitrogen, phosphorus, or potassium limited, would the co2 do any damage? is it not beneficial to lower light tanks, as I have read? don't get me wrong, I don't *want* to waste CO2, I'm just curious... thanks


Always remember that the damage is caused by the limiting factor. Wether high tech or low tech, if you tank for example is nitrogen limited then the damage seen will be _nitrogen _starvation. CO2 will not cause damage unless the concentration level is not held constant. Fluctuating CO2 levels give the advantage to algae because highe plants cannot adjust the level of their carbon uptake mechanism (certain enzymes) as quickly as algae can with theirs. The damage is therefore caused by having the CO2 level fall. Growth, reproduction and repair are put on hold while enzymes are re-configured to match the new environment. Therefore stability of CO2 levels is more important than the actual levels in a low tech tank.

Carbon is a nutrient and is always appreciated by plants. Stop thinking about CO2 in terms of toxicity, or whether it's more important/less important than some other parameter. Add it if you've got it, keep it stable and you'll see higher growth, period. If you don't want to add it fine, but keep that ambient level stable by reducing the water change frequency. A carbon alternative is Seachem Excel, (or, some plants can strip bi-carbonate from the water) so in that sense, no you don't "need" CO2 in a low tech tank, but you need to understand what carbon is and does and that way you can make the right choices (or at least understand the ramifications of your choices).

Cheers,


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## Oqsy (Jul 3, 2004)

i put the brakes on the tank today, removing the ODNO leads from the light, making it just 60w NO fluorescent. I will also stop dosing, wipe my javas and anubias clean of algae, and see where things go from there. is it a good or a bad idea to do a weak bleach dip to get the hair algae off my DW/attached plants with a strong dechlor soak? i know that rome wasn't built in a day, but nero did fiddle while it burned. (that didn't make sense... just let it go)... 

anyway, i'm already seeing more of my apistos since backing the lighting down. 

Oqsy


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## aquaverde (Apr 15, 2003)

> Sorry, but I disagree with this statement. EI is based fundamentally on the concept of nutrient deficiency avoidance by dosing to slight excess, which includes CO2. Inappropriate limiting CO2 is just as damaging as inappropriate limiting of NO3. The actual driver is light.


And I must disagree with you. Light is not the driver. CO2 is.

EI is a method of nutrient dosing in a CO2-enriched tank without the use of test kits. It was developed for CO2-enriched tanks, regardless of whether the light level is “high” or “low”. EI is not appropriate if CO2 is not being used.

My point is simply that if you dose CO2, you need to dose nutrients. The statement from the latest version of EI on barrreport.com is, “This method is specific for CO2 enriched systems with higher light but works even better with lower light CO2 enriched tanks”.



> If you look at the parameters of the baseline EI 20 gallon tank you'll see that the illumination is 5.5wpg. I'm unsure exactly how Tom Barr arrived at this value. It could be that he considered that this would be the top end for most tank owners or, I suspect that it's more likely that his studies indicated that more light beyond this value does not significantly increase nutrient uptake.
> 
> Based on this maximum light level driving the maximum nutrient uptake the dosing levels guarantee that there will not be any dificiency. The NO3, PO4, micro and CO2 target levels in the dosing scheme are based on this maximum uptake level all driven by the maximum light.”


I think by assuming light is the driver, you have missed the point. Setting a max is based upon the revelation, “An important aspect of this method is the knowledge that excess nutrients do not cause algae blooms” (The Estimative Index). We don’t want to under-dose, so we set a max uptake level. “Overdosing” is not a problem. This is opposite to the approach that was taken for so many years (e.g. Conlin-Sears). Besides, this light level is not the max. There are some running 7 and 8wpg. They have a second mortgage to pay for the tanker truck of Flourish in the front yard, though (almost a joke).



> You needn't live on the extremes however. No one says that you can't have a "medium tech". As long as you stay below the 2wpg (more or less) to avoid engine revving, you can still inject C02 or add Excel and acheive 2 to 6 times more growth as compared to non carbon supplementation.


That’s not the point. The point is, if you bottom your nutrients your plants will stop growing. But guess what will grow! (We are talking specifically about CO2 injection, not use of Excel, which has algaecidal tendencies). 

If you are expecting to get 2-6x growth rate and you don’t dose N and P, please explain where it is coming from to sustain that kind of growth.



> I'm hard pressed to belive that there is any correlation between CO2 deletion and algae removal. CO2 level increase is one of the main factors that trigger algae dormancy, so something else must have changed along with the loss of CO2. You can't draw this conclusion unless you can verify that all other variables remained constant and that only the CO2 changed.


My experience is anecdotal, by no means scientific proof, as I already stated. There have been studies done by Barr and some German aquarists that suggest high consistent levels of CO2 inhibit BBA. Inconsistent levels of CO2 (associated mostly with DIY) are known to trigger BBA. This is why Barr discourages water changes on non-CO2 tanks. I had DIY on my tank, and I believe the BBA (not the other types) was there due to inconsistent levels.

Filamentous algae just loves high CO2. Where did you get the idea CO2 level triggers algae dormancy? 


> Huh??? Stems do just as well as other crypts in low tech. They just don't grow as fast as stems in a high tech environment. Hygros, for example can dominate any setup if you allow them to. Of course that's assuming you dose the water column. If you don't dose, then yes, root feeders will have an advantage. You still dose with a low tech, you just don't have to dose nearly as often as with high powered laser beam setups.


I was stating my personal preference. Didn’t actually go into why, did I?



> Always remember that the damage is caused by the limiting factor. Wether high tech or low tech, if you tank for example is nitrogen limited then the damage seen will be nitrogen starvation.


I’m curious. What would you advise for a low light CO2-injected setup that is nitrogen limited?

I don't fully understand what you're disagreeing with.


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## aquaverde (Apr 15, 2003)

Oqsy said:


> i put the brakes on the tank today, removing the ODNO leads from the light, making it just 60w NO fluorescent. I will also stop dosing, wipe my javas and anubias clean of algae, and see where things go from there. is it a good or a bad idea to do a weak bleach dip to get the hair algae off my DW/attached plants with a strong dechlor soak? i know that rome wasn't built in a day, but nero did fiddle while it burned. (that didn't make sense... just let it go)...
> 
> anyway, i'm already seeing more of my apistos since backing the lighting down.
> 
> Oqsy


The bleach dip was developed by Paul Krombholz specifically to handle filamentous algae. It works really well on tough species like Anubias, but stem plants can suffer. It's a lot of work, too, and to really get rid of the problem, you have to bleach all the plants as well as the tank and equipment. Considering how long Anubias leaves last, you might want to do the bleach thing for them, at least. Give you a clean start, so to speak.


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## Oqsy (Jul 3, 2004)

ok, now i'm really lost... let me put whole thing another way.
I have a 20H tank with 60 watts NO lighting and pressurized CO2 at ~35-40ppm. at this lighting level, what would the appropriate dosing schedule be? keep in mind I'm getting my macros from KNO3, KCl, and Fleet; micros from Flourish. 

i cleaned up the anubias, java ferns, and driftwood with a very very diluted spray of bleach and some paper towels, rinsed very thoroughly, and dechlored. the other plants in the tank are virtually algae free, so I didn't risk burning them up with bleach... equipment is pretty much the same way. I know this doesn't eliminate the algae from the system(can't afford UVS at the moment anyway), but it helps give the plants the advantage if my other parameters are indeed correct. 

Oqsy


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## sarahbobarah (May 20, 2005)

Hey, my brother's dog was named Nero.....

I have a 20GH with only 38 watts over it (the fixture and flo tube it came with along with a 30 inch flo strip light - I know it's ugly but I don't care) No CO2, no ferts, and only landscaping gravel). How's that for low tech?

I'm growing swords: amazon, ozelot, melon (?). Everyone/thing is happy. I truly think with the plants you listed, you can totally get away with nothing but fish poop. So sit back and enjoy your low maintenance tank!

roud:


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## aquaverde (Apr 15, 2003)

Oqsy said:


> ok, now i'm really lost... let me put whole thing another way.
> I have a 20H tank with 60 watts NO lighting and pressurized CO2 at ~35-40ppm. at this lighting level, what would the appropriate dosing schedule be? keep in mind I'm getting my macros from KNO3, KCl, and Fleet; micros from Flourish.
> 
> Oqsy


Just dose per EI. Dropping the light to 3wpg shouldn't change things for your routine. What were you dosing up to now?


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## Oqsy (Jul 3, 2004)

i've been dosing:

odd days:
1/4 tsp. KNO3
4 drops Fleet
KCl solution dosed to an extra 10ppm K+ in addition to the K from KNO3

even days:
2.5ml flourish 

day seven: nothing

50-60% WC weekly...

Oqsy


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## aquaverde (Apr 15, 2003)

I don't think I'd change anything. Everything's growing, right? (not talking about the Anubias)


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## Oqsy (Jul 3, 2004)

lysimachia, chain sword, rotala, and java fern are doing well... 
thread algae is doing better  
lileaopsis brasiliensis is staying green, but not really spreading. 

i'm currently talking with someone about quite a few bronze wendtii crypts and also looking into other types of anubias(frazeri, afzelli, caladiifolia, congensis, coffeefolia, heterophylla, etc) then I'll most likely remove the lysimachia, rotala, and probably the chain sword and stick with the "easier" plants... ie crypts, anubias, java ferns... one high maintenance tank is enough for now  

besides, this tank is less than 3" from my high-tech, high-light, high-fert, high-co2, high-energy bill, high-stakes 29 gallon. it should make an interesting contrast to have them side by side for comparison and contrast.

Oqsy


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## ceg4048 (Mar 26, 2004)

aquaverde said:


> I don't fully understand what you're disagreeing with.


OK, it's so easy to trip over one's own shoelacese so let's see if we can clarify. I'm fundamentally disagreeing with this statement:



aquaverde said:


> [That in an ecosystem] Light is not the driver. CO2 is.


Put aside any dosing schemes for the moment in order to examine the system dynamics. First of all, plants exist (can we use the expression "evolve"?) fundamentally in the form that they do primarily because of the existence of light, not because of the existence of CO2. The entire planet's ecosystem is driven by the sun. Since there happens to be an abundance of carbon, nitrogen etc. the light engine is fueled by the elements such as carbon. Plants photosynthesize, remember? The process of Photosynthesis involve using light energy to convert CO2 and other compounds into sugars. Please read The Barr Report Newsletter March 2005:

"1. Light is the major energy input to aquatic ecosystems.
2. Photosynthesis and metabolism is driven by the amount of light energy.
3. Light plays a dominate role in lakes and a streams with respect to aquatic Macrophytes.
4. Most aquatic Macrophytes exist in the top two meters of the water column....."

If we use this analogy of a light engine fueled by the ambient elements it's easy to see that if we are low on fuel the engine stalls. What I'm saying therefore is that the primary difference between low tech and high tech is functionally low light versus high light. At low light and thus low photosynthesis we need less fuel, therefore we can get away with less dosing and less carbon. Adding more carbon and more nutrients helps to some extent but the effect will max out proportionally to the light level.

You accurately quote from the EI article that: "...This method is specific for CO2 enriched systems with higher light but works even better with lower light CO2 enriched tanks..." but I believe you mistakenly draw the conclusion that CO2 is primary. In fact, the very next sentence in that paragraph from which you quoted states
"...I suggest 30ppm of CO2, while a tank with 2 w/gal might be okay with 15-20ppm, many with power compact bulbs and reflectors need to have their CO2 levels higher, 20-30ppm range is optimal for the lighting period. This was found by adding more CO2 until there was no net gain in plant growth while keeping the nutrient and lighting levels consistent during the testing period..." This clearly shows that higher light levels require more fuel (carbon) while lower light levels require less. I suppose you could argue that the reverse is true, i.e, that lowering the CO2 level requires a drop in the light level, but really, the engine analogy holds here in that you are lowering the fuel level so he engine slows.

Furthermore, the EI article goes on to say:

"Returning back to non CO2 planted tanks after gaining this knowledge at high light and CO2 enrichment allows some fairly good predictions/correlations of uptake rates for non CO2 planted tanks as well. The rate of uptake is reduced due to less light and less CO2. I generally use about 6 to 1 slower uptake rate ratio for non CO2 tanks but the fish loading can change this ratio. Basically the non CO2 tank grows 6-10x slower than a CO2 enriched tank."



aquaverde said:


> Filamentous algae just loves high CO2. Where did you get the idea CO2 level triggers algae dormancy?


Wrong. Filamentous algae just love NH4 and light. I got the idea from Mr. Barr himself. Also I stated that CO2 s one of the main factors. Please review the following thread: http://www.barrreport.com/forums/showthread.php?t=387
Where did you get the idea that filamentous algae loves high CO2? People following EI claim a reduction in all types of algae with the suggested 20-30ppm CO2.



aquaverde said:


> Quote:
> Huh??? Stems do just as well as other crypts in low tech. They just don't grow as fast as stems in a high tech environment. Hygros, for example can dominate any setup if you allow them to. Of course that's assuming you dose the water column. If you don't dose, then yes, root feeders will have an advantage. You still dose with a low tech, you just don't have to dose nearly as often as with high powered laser beam setups.
> 
> I was stating my personal preference. Didn’t actually go into why, did I?


That's right, you didn't and you should have. Your response was within the context of answering Oqsy's question regarding CO2 and dosing in a low tech environment, remember? It was impossible to determine from the context that you were stating a general aesthetic prefererence of crypts to stems. Apologies.



aquaverde said:


> If you are expecting to get 2-6x growth rate and you don’t dose N and P, please explain where it is coming from to sustain that kind of growth.


Yes, I'm sorry, I made the same error as I did not clarify that I assume that all other dosing was in effect. It is pointless to stop dosing, either macros or micros. In a low tech tank everything is simply scaled back.



aquaverde said:


> ...Setting a max is based upon the revelation, “An important aspect of this method is the knowledge that excess nutrients do not cause algae blooms” (The Estimative Index). We don’t want to under-dose, so we set a max uptake level. “Overdosing” is not a problem. This is opposite to the approach that was taken for so many years (e.g. Conlin-Sears). Besides, this light level is not the max. There are some running 7 and 8wpg. They have a second mortgage to pay for the tanker truck of Flourish in the front yard, though (almost a joke).


You know, I re-read the article and I found this statement:

"...The reason I chose this high light intensity was to reduce the time before an algae bloom would occur and prevent competition for light. If algae was to occur due to higher nutrient levels, if would occur when the light, CO2 and nutrients were non limiting for both sets of variables. With less light, down to a point (Light compensation point, the LCP), we can assume less uptake and less issue maintaining a “stable range” of nutrients. It is much more difficult to tease apart the relationships when the rate of growth is slower (e.g. less light), it takes more time to note differences in plant growth and places less stress/growth rate on the system..."

You can see that although the parameters used to develop the EI dosing was high light, high CO2 and high everything else, it was in a way a technique of normalization in which everything can be scaled down proportionally from the top.



aquaverde said:


> I’m curious. What would you advise for a low light CO2-injected setup that is nitrogen limited?


Well, I mean..um..add nitrogen? (is this a trick question?) Again, I think we lost sight of the context here. Remember that Oqsy was asking whether adding CO2 to a tank suffering from nutrient dificiency would cause additional damage (at least I thought that's what was being asked). I was trying to explain that whatever limitations were in effect, whether it be N, P or K, the damage would be as a result of that limitation, not due to any CO2 addition. Perhaps that was what you were trying to say in your response but I found it confusing. 

I think everyone agrees to avoid nutrient deficiency but the question I perceived in this thread was how to accomplish that in a lower maintenance tank and whether CO2 addition is relevant in such a tank. I apologize if I misread the posts but others reading the posts may have the same confusion. FYI there is an EI scheme for non-CO2 tanks here: http://www.barrreport.com/forums/showthread.php?t=395

In Oqsy's case with 3wpg and injected CO2, this doesn't really qualify as low tech though.

The discussion about whether light is the driver versus CO2 is important only in the sense of understanding the tank dynamics and in order to help troubleshoot problems that arise. If algae is a problem for example it's better to understand that lowering the light is a more reliable solution than lowering the CO2, and that increasing the CO2 is a better bet than increasing the light. That's why the driver question is important.

Cheers,


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## aquaverde (Apr 15, 2003)

> OK, it's so easy to trip over one's own shoelacese so let's see if we can clarify. I'm fundamentally disagreeing with this statement:
> 
> 
> > Originally Posted by aquaverde
> ...


Aha. Now I see the problem. You are trying to tell me about ecosystem dynamics and photosynthesis. I was talking about what determines EI.

First, you quoted me here and disagreed with me:


> Originally Posted by aquaverde
> The basic thing that drives EI is CO2 enrichment, not high light. If you want to stop dosing, pull the CO2 off the tank as well. With the plants you have, I think you don’t need CO2 anyway.


My statement, “The basic thing that drives EI is CO2 enrichment” would have been clearer if I had said “The basic thing that drives *the use of* EI is CO2 enrichment.”

Does that make it any clearer? Here is what I am saying: if you use CO2, use EI. Or, again: if you inject CO2, you will have to continue dosing.

Usually I’m articulate enough to get my point across, but in this case twice I failed. 

The point on EI is that it is designed for CO2-enriched systems. Non-CO2 is a completely different method. If you want to define high tech exclusively as high light, you give the impression you don’t include CO2 injection. In fact, light intensity high enough to be termed “high light” will necessitate CO2 injection, ergo “high tech”.

By the way, I am not arguing the mechanics of, or importance of, or physiology of either light or photosynthesis. I was arguing the importance of CO2 as the determining factor in using EI. I used to think high light was it, but Tom told me himself not to confuse the methods. CO2 enrichment was the determiner for the _method_, not light level. 

Here's Tom's response to me on APD on the subject:
http://fins.actwin.com/aquatic-plants/month.200309/msg00027.html



> > Originally Posted by aquaverde
> > Filamentous algae just loves high CO2. Where did you get the idea CO2 level triggers algae dormancy?
> 
> 
> ...


I think things got generalized somewhere, because neither EI nor CO2 levels will inhibit all algae types. To be fair, it’s a distinction Tom does not make very often, and I almost think he doesn’t like to mention it. I’m talking chladophora, spirogyra, that sort of algae. I read the thread you posted and I know it’s early in the morning here, but I don’t see Tom saying anywhere in it that CO2 will suppress this type of algae. I have asked Tom directly if changing water parameters will get rid of this algae the way it will other types and he said “no”. Also, I believe it gets into the tank through infection on a new plant and not through airborne spores. Some other types can be controlled through CO2 and EI, but not this.

You’re a barrreport.com member. Check this out with Tom.



> I think everyone agrees to avoid nutrient deficiency but the question I perceived in this thread was how to accomplish that in a lower maintenance tank and whether CO2 addition is relevant in such a tank. I apologize if I misread the posts but others reading the posts may have the same confusion. FYI there is an EI scheme for non-CO2 tanks here: http://www.barrreport.com/forums/showthread.php?t=395
> 
> In Oqsy's case with 3wpg and injected CO2, this doesn't really qualify as low tech though.
> 
> The discussion about whether light is the driver versus CO2 is important only in the sense of understanding the tank dynamics and in order to help troubleshoot problems that arise. If algae is a problem for example it's better to understand that lowering the light is a more reliable solution than lowering the CO2, and that increasing the CO2 is a better bet than increasing the light. That's why the driver question is important.


I have two non-CO2 tanks at this point, and they are a real pleasure. One is and always has been 90% low light plants. I have 2.25wpg over that tank and it is pristine.

Just on a side note, I ran this tank with no fish at all, and I also ran a CO2-injected tank with no fish at all. Both were cleaner looking tanks algae-wise than anything I’ve ever had. I ran into a problem and had to put a half dozen fish into one of them and boy, did I get an algae bloom for that. I reckon there was so little NH4 in the tank prior to adding the fish that I had lost my nitrifying bacterial colony and the result was a mess.


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## aquaverde (Apr 15, 2003)

Oqsy said:


> lysimachia, chain sword, rotala, and java fern are doing well...
> thread algae is doing better
> lileaopsis brasiliensis is staying green, but not really spreading.
> 
> ...


I couldn't be happier with my non-CO2 20g. It almost takes care of itself. the aquascape lasts months, not a week. The most maintenance I do is scraping dust off the glass from time to time. And trimming moss. ceg4048 is right about some of the typically high-light plants doing OK in the lower lighting, too. When it comes right down to it, my 65 fast tank satifies all my tinkerlust. :wink:


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## equinecpa (Sep 23, 2004)

James;

I have a tank that I want to convert to low-tech: It's a 30G Hex with 56w of PC over it. I've been plagued with every kind of algae imaginable trying to achieve balance between C02 and ferts. I even have a UV on the tank - but that just knocks out the GW the algae on the plants, glass etc keep on growing- I give up...going low tech.

What plants do you have in your 20? What seems to do well? I'd love to go the fish poop method of fertilizing. What is your substrate?

Carolyn


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