# Combine Seachem Matrix and DeNitrate?



## AbbeysDad (Apr 13, 2016)

I think you're barking up the wrong tree. First, even a highly effective bio-filter will do little to combat algae of any kind. Matirx and DeNitrate will not help you. These are pumice stone products that promise to promote both aerobic and anaerobic bacteria to complete the N2 process by converting ammonia->nitrites->nitrates->nitrogen gas. This does not affect algae.
I used both (Matrix & DeNitrate) products for nearly 2 years to attempt to culture anaerobic bacteria to process nitrates into N2 gas. First, I added an additional AC70 filter with an AC30 impeller filled with a mix of Matrix and DeNitrate. Later, I 'invented' a filter that used a LOT of the media and lots of Stability with NO success. I was never able to reduce tank nitrates!
In the end, I find that bio-sponge is perhaps the best bio-media and culturing anaerobic bacteria in our highly oxygenated FW tanks is very difficult, if not impossible.

I'd suggest you invest in sufficient lighting to heavily plant your tank. Use bio-sponge material in your filter. For the brown algae or any free floating algae or diatoms, perhaps consider a UV sterilizer.


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## Quizcat (Dec 21, 2014)

*Here's why...*

Thanks for your reply, and I appreciate all the experimentation you've done with respect to Matrix and De*Nitrate. Perhaps I am barking up the wrong tree with a Matrix/De*Nitrate solution, it could be, but... 

I see it as a three front war actually, Nitrogen Cycle, Silicates, and Phosphate levels. I theorize that silicates and phosphates may be just as responsible as the Nitrogen Cycle. I think these three issues have to be addressed to resolve the brown diatom issue.

The term "Brown Algae" is a misnomer. Brown Algae (Diatoms) are not Algae. I don't have any issue with actual algae whatsoever, which makes me think my lighting is under control, along with the fact that I've done considerable experimentation with my lighting to no avail. There's wide disagreement in the forums and online as to whether more or less lighting has any effect whatsoever on brown diatoms (brown algae). I've personally concluded that lighting really has little or no appreciable effect on their proliferation in the tank based on my own experimentation. 

Brown Diatoms flourish from silicates being in the water, which with our hard water occurs every time I do a water change or top-off the tank, and silicates and phosphates accumulate every time you top off the tank. Brown Diatomes (Brown Algae) like phosphates (which is tap water related related), and they like Nitrates too. That's why I've been experimenting with Purigen and Phosguard, and want to improve the Nitrogen Cycle, in an effort to help reduce silicates, nitrates, and phosphates in the tank, which reduces the environment for brown diatoms to flourish.

I've been running a Deep Blue UV Sterilizer for the entire time that the brown diatoms have been a problem. UV Sterilizers will only help with parasites, and I do like having a UV sterilizer in the mix to reduce the potential for parasites in the water. But, brown diatoms aren't parasites, so I don't really expect the UV Sterilizer to help me much with brown diatoms.

I've had planted tanks in the past, and frankly, they can complicate this issue because you have to simultaneously worry about properly nourishing them, due to dosing nutrients and delivering proper lighting. So, for now, I've omitted plants so I can focus on the brown algae without having to simultaneously introduce another criteria to worry about, of having to properly nourish the plants without the balancing act of making sure I am not nourishing the brown algae (diatoms). 

So, while I might still be barking up the wrong tree with Matrix and De*Nitrate, with lighting eliminated, plants not being an option for now, and UV already running in the tank, that leads me back to the Nitrogen Cycle, Silicates, and Phosphates. 

So, my theory about the bio-wheel on the previous Penquin filter not doing it's job was my first lead into a conclusion that the Nitrogen Cycle is part of the issue, and the idea of adding plants also suggests that same avenue of thought. 

So, the cheapest fix, if in fact the bio-wheel didn't help to establish an adequate bio-filter in the tank, is to change out the filter design by going to the Aquaclear filters, which I already have in my stash (cheap), and to add the Matrix to the Aquaclear 50 chamber (cheap), and also to experiment with De*Nitrate in the Aquaclear 30 chamber too (cheap), in an effort to establish a better functioning bio-filter. 

Once the new bio-filter is established, and my test kit confirms that the cycle is mature, I plan to use Phosguard (cheap) to remove silicates when I do water changes and top-offs. I haven't decided yet whether, once the nitrogen cycle is established, to use Purigen to remove ammonia, nitrites, and nitrates. That might be the time to introduce some live plants instead, but only after I'm convinced I have the diatoms under control.

I am going to try your suggestion of a bio-sponge in one of the Aquaclear filters, probably the Aquaclear 30, where the De*Nitrate is also being housed right now as well. I've heard good things about using a bio-sponge, and your suggesting it reminded me to move forward with that. 

Is there a particular brand of bio-sponge you've had the most success with and can recommend?

I've even started to research building a DIY Sulfur/Matrix Denitrator/Reactor Canister Filter. It's one of those DIY projects that are good for winter time. It's cheap to make too, and most parts are easy to get at Lowes, so why not play with it? 




AbbeysDad said:


> I think you're barking up the wrong tree. First, even a highly effective bio-filter will do little to combat algae of any kind. Matirx and DeNitrate will not help you. These are pumice stone products that promise to promote both aerobic and anaerobic bacteria to complete the N2 process by converting ammonia->nitrites->nitrates->nitrogen gas. This does not affect algae.
> I used both (Matrix & DeNitrate) products for nearly 2 years to attempt to culture anaerobic bacteria to process nitrates into N2 gas. First, I added an additional AC70 filter with an AC30 impeller filled with a mix of Matrix and DeNitrate. Later, I 'invented' a filter that used a LOT of the media and lots of Stability with NO success. I was never able to reduce tank nitrates!
> In the end, I find that bio-sponge is perhaps the best bio-media and culturing anaerobic bacteria in our highly oxygenated FW tanks is very difficult, if not impossible.
> 
> I'd suggest you invest in sufficient lighting to heavily plant your tank. Use bio-sponge material in your filter. For the brown algae or any free floating algae or diatoms, perhaps consider a UV sterilizer.


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## AbbeysDad (Apr 13, 2016)

Quizcat said:


> Is there a particular brand of bio-sponge you've had the most success with and can recommend?


I have two AC70 filters with AC50 impellers on my 60g. They are both configured the same. I use a thin coarse pad (like scotchbrite) to trap detritus, then a standard AC70 sponge, a thinner/finner biosponge, another AC70 type sponge, then a layer of polyester fiber for polish. (there are numerous bio-sponge choices on Amazon).

As food for thought, I've attached a photo of the Matrix/DeNitrate filter I built to attempt the reduction of tank nitrates. The water siphoned in to the bottom and was pulled out by a Tom Aqualifter (3.5gph) pump. I repeatedly dosed with Seachem Stability but could never get anaerobic bacteria to culture and tank nitrates were never reduced.

Live plants were the answer for me as they use ammonia and (some) nitrates as their N2 source indirectly reducing nitrates.

footnotes: 
1) Consider higher quality foods that use less/no grain filler/binders (resulting in less fish waste). This also reduces phosphates.
2) API Nitra-Zorb is an excellent nitrate absorber that can be recharged many times in salt water.
3) I never saw much if any real improvement with Purigen and seem to trap more with simple polyester fiber.


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## WaterLife (Jul 1, 2015)

Okay, I didn't read any of the above because it's so long (what's the main question/reason for wanting/needing to combine the two?), but maybe this bit of info may help.

Seachem denitrate, matrix and pond matrix are all EXACTLY the same media, just different sizes.

The smaller the pebble size, the more surface area (per volume) for nitrifying bacteria. So in a higher flow filter, denitrate would actually boast the most surface area per volume. Though, it might be overkill as it is. (I don't remember the cost of denitrate vs matrix, so that factors in. Think matrix is cheaper, so that's that)

Denitrate is just meant for very slow waterflow to grow anaerobic bacteria to convert nitrate into nitrogen gas. Now if you were trying to denitrify in a higher flow filter, you would be better off using the larger pond matrix because the deeper internal pores will become clogged, creating low flow/oxygen areas (anaerobic conditions) within the larger media, so that way, anaerobic bacteria can grow internally.


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## Quizcat (Dec 21, 2014)

Sorry to be so long winded, but I wanted you to have all the parameters so you could give some good advice.

I didn't know that the Pond Matrix might be the better choice under my circumstances, since I'm trying to convert Nitrates to gas...and toward that end, cultivate anaerobic bacteria in a box filter with higher flow rates.

But, yeah, just trying to grow more anaerobic bacteria, and do it on the cheap for now, versus buying a commercial denitrator/reactor.

Matrix, according to Seachem, is better at cultivating aerobic bacteria, which is fine, but I want good performance converting Nitrates too, so I want to cultivate a nice colony of anaerobic bacteria.

I've got a ton of Lava Rock in my stash...
Do you think that would work better in the Aquaclear filter? 
Or sitting in the bottom of the tank???? 
Better than putting Matrix, De*Nitrate, or Pond Matrix in the filter???? 

I did have a small bag of De*Nitrate just sitting in the bottom of the tank to resolve the flow issue in the filter, but it's kind of unsightly with respect to tank presentation sitting at the bottom of the tank.



WaterLife said:


> ...it's so long


Bump: Yeah, that's what is so frustrating...you read all the positive reviews, then things never seem to work out when you put all the effort in. Seems like you're following the slow flow rate parameters, so I'm not sure why it didn't work. But experiences like yours has me thinking twice about whether to build a Denitrator Canister, as well as whether Seachem's matrix's are what I need. 




AbbeysDad said:


> As food for thought, I've attached a photo of the Matrix/DeNitrate filter I built to attempt the reduction of tank nitrates. The water siphoned in to the bottom and was pulled out by a Tom Aqualifter (3.5gph) pump. I repeatedly dosed with Seachem Stability but could never get anaerobic bacteria to culture and tank nitrates were never reduced.


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## Maryland Guppy (Dec 6, 2014)

Quizcat said:


> De*Nitrate requires a flow rate of less than 50 GPH in order to nourish the anaerobic bacteria. Seachem advises that anything higher than 50 GPH will starve the bacteria of nutrients, and the anaerobic bacteria will die.
> 
> Seachem recommends a canister filter for De*Nitrate to reduce the oxygen levels so that the anaerobic bacteria can colonize and flourish within the De*Nitrate media. But, I can't seem to find a canister filter anywhere that has less than a 50 GPH flow rate. Most canister filters process at much higher rates. I looked at the Eheim Classic 2211, but it processes at a rate higher than 50 GPH as well.
> 
> I do really have a lot of respect for Seachem, but why do they develop a product, then recommend that it should be used in a canister filter that doesn't exist (ie: less than a 50GPH flow rate)..


The low flow you require for DeNitrate is no different than hooking up a UV on a canister.
Tap the filter discharge with a "T" and a valve to control flow, some DIY chamber would work.
Measure with a cup and do the math to set the valve/flow.



Quizcat said:


> and Purigen to reduce ammonia, nitrite, or nitrates if they get high. Do you recommend Phosguard in there for times when I top-off the tank? What about Purigen?
> 
> not to mention whether it would be wise to eventually incorporate other chemical treatments like Phosguard and Purigen.


I cannot speak for phosguard but when planted you will want a 10:1 ratio of NO3O4.

Purigen is an organic scavenging resin, not at all a chemical treatment.
It releases nothing into your water.
Purigen absorbs and collects organics before they break down into their lowest form being NH3.

From Seachem website.
"Purigen® controls ammonia, nitrites and nitrates by removing nitrogenous organic waste that would otherwise release these harmful compounds."

Matrix is pumice, most likely better than lave rock although I use lava rock in all my filters.
Pumice can be had on the web cheap, you can buy the size aggregate you want.


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## Quizcat (Dec 21, 2014)

Yeah, good idea, I hadn't thought of that...I think a 29 Gallon tank takes about 350ml of De*Nitrate in the chamber. 

I guess the question now is which media is the best for cultivating anaerobic bacteria, and exactly how much of it to use based on the selected media, each type having different pore sizes. Apparently, with respect to De*Nitrate, it needs to be less than a 50GPH flow rate. I wonder if that applies to Lava Rack, etc...

I've read of several accounts where guys that built DIY denitrating chambers operating at very low flow rates, around 3.2 GPH, reported that they didn't have a lot of success. I wonder if the flow rate at 3.2GPH is too slow, or fast for that matter, depending on the particular media (Pore Size).



Maryland Guppy said:


> The low flow you require for DeNitrate is no different than hooking up a UV on a canister. Tap the filter discharge with a "T" and a valve to control flow, some DIY chamber would work. Measure with a cup and do the math to set the valve/flow.


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## AbbeysDad (Apr 13, 2016)

Quizcat said:


> Sorry to be so long winded, but I wanted you to have all the parameters so you could give some good advice.


Only if it gets read. 



Quizcat said:


> I didn't know that the Pond Matrix might be the better choice under my circumstances, since I'm trying to convert Nitrates to gas, and toward that end, cultivate anaerobic bacteria in a box filter with higher flow rates.
> But, yeah, just trying to grow more anaerobic bacteria, and do it on the cheap for now...because Matrix, according to Seachem, is better at cultivating aerobic bacteria, which is fine, but I want good performance converting Nitrates too, so I want to cultivate a nice colony of anaerobic bacteria.


The Aquaclear 20, 30, 50 & 70 all use the same motor with interchangeable impellers. At one point, I filled one of my AC70's with a Matrix/DeNitrate mix and used an AC20 impeller for a slow flow. When that didn't reduce nitrates, I built the additional external filter. I don't believe I was ever able to culture anaerobic bacteria in spite of the marketing claims.



Quizcat said:


> I've got a ton of Lava Rock in my stash...Do you think that would work better in the Aquaclear filter or sitting in the bottom of the tank, better than putting Matrix, De*Nitrate, or Pond Matrix in the filter? I did have a small bag of De*Nitrate just sitting in the bottom of the tank to address the flow issue, but it's kind of unsightly with respect to tank presentation.


Matrix/DeNitrate pumice is a form of lava rock. I don't know if generic lava rock has the deeper pores you'd need for anaerobic bacteria culture.



Quizcat said:


> Bump: Yeah, that's what is so frustrating...you read all the positive reviews, then things never seem to work out when you put all the effort in. Seems like you're following the slow flow rate parameters, so I'm not sure why it didn't work. But experiences like yours has me thinking twice about whether to build a Denitrator Canister, as well as whether Seachem's matrix's are what I need.


Nope. After two years of serious experimentation ALL of the Matrix/DeNitrate is in a bin in the basement. I'm using bio-sponge in the filters, 3-4" silica (pool filter) sand substrate and heavily planted low tech.


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## Quizcat (Dec 21, 2014)

Glad you mentioned that...I already thought of getting another impeller for the Aquaclear 30, maybe shortening, or even removing, a few of the fins, in hopes that it would cut down the flow rate. Seemed to be a very good idea at the time, only a few bucks for the spare impeller. But, it sounds like that would have been a dead end. 

So, do you think it's the media itself? If that's the case, I wish there was a media alternative that would work...

I still have the media that came with the Aquaclear filters called BioMax...little 1/4" squares, lots of pores and voids, but not sure if Biomax has a reputation for cultivating anaerobic bacteria better than anything else on the market. 



AbbeysDad said:


> The Aquaclear 20, 30, 50 & 70 all use the same motor with interchangeable impellers. At one point, I filled one of my AC70's with a Matrix/DeNitrate mix and used an AC20 impeller for a slow flow. When that didn't reduce nitrates, I built the additional external filter. I don't believe I was ever able to culture anaerobic bacteria in spite of the marketing claims.


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## Maryland Guppy (Dec 6, 2014)

https://www.wayfair.com/Featherock-Inc-Natural-Pumice-Gravel-GRAVEL-FTHR1012.html?PiID[]=19298044&source=hotdeals

Here is an example from a very quick search.
Different size aggregate can even be selected.

More faith would be in pumice as opposed to traditional lava rock.
Seems like each piece of pumice is more uniform and consistent.
All the lava rock I have seems to have way different densities among the pieces.


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## WaterLife (Jul 1, 2015)

You can find this quote in the last sentence a Seachem Tech wrote "If you need to use a higher flow rate, than stick with Matrix™or try Pond Matrix™, both of which support anaerobic denitrification at higher flow rates."
Creating Anaerobic Bacteria with Pond Matrix - Seachem Support Forums

Lava rock, while it looks to have a lot of pores, those pores are only on the surface. The pores do not create a inner tunnel network like other porous material such as ceramic, Matrix, sintered glass, etc. So it doesn't have any internal surface area like the other medias. So lava rock is pretty much useless for anaerobic bacteria culturing unless you only use it in a very slow flow filter.

For slower water flow you can simply use a ball valve. Using mechanical or any media to slow down flow, helps too, but may not slow it down quite enough. (at least until things start clogging). Nitrate reactor

Denitrification for cheap, plants would probably be the fastest option (aquatic or emersed house plants). 
There is also deep sand beds (yes, it works in freshwater too).
Or just do water changes  Removes organics/TDS too
Anaerobic autotrophs can take awhile to cultivate.

This website has a ton of knowledge on all aquatic stuff. Worth reading if you are interested.
Hydrogen Sulfide in Aquariums
Deep Sand Bucket or Tank | Nitrate Removal Projects
Aquarium Nitrogen Cycle | Cycling Methods | Ammonia & Nitrates

Dentrifity resins are expensive.


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## Quizcat (Dec 21, 2014)

According to Seachem, I should only need about 300mL of Pond Matrix for a 30 Gallon tank, which is roughly the same amount recommended for De*Nitrate. So, I actually have room for a bag of both of them in the Aquaclear 30 chamber. 

Does anybody know of any reason why slowing down the flow rate below 50 GPH, and having Pond Matrix in there, along with De*Nitrate in the chamber, slowing down the flow just to accommodate the recommended flow rate for De*Nitrate, would have any negative effect upon cultivating aerobic bacteria in Pond Matrix? 

I can't really see why it would...It looks like the smallest packaging for Pond Matrix is 1 Liter, and it runs about $19.00 at Amazon.com.



WaterLife said:


> You can find this quote in the last sentence a Seachem Tech wrote "If you need to use a higher flow rate, than stick with Matrix™or try Pond Matrix™, both of which support anaerobic denitrification at higher flow rates."


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## WaterLife (Jul 1, 2015)

The two different environments are what determine suitable living conditions for the bacteria. The aerobic nitrifiers like having higher oxygen levels, while the anaerobic denitifiers like having close to no oxygen. The very definitions of aerobic and anaerobic.

Aerobes literally need the oxygen to function/live. So the lack of oxygen dictate how much (little or possibly even none at all) aerobes can be supported with the low oxygen supply
. 
Anaerobes are effected by the presence of oxygen molecules, from stopping growth, metabolism, or even killing off the anaerobic bacter.

If you are going to have a <50 GPH nitrate reactor, then just go with denitrate (or matrix if it's more cost efficient). I only recommended pond matrix if you are using a higher flow rate. No harm in using it though, just not as space efficient.

Now I'm pretty sure you can have a small amount of aerobic nitrifiers in the slow flow nitrate reactor, just not nearly as much or efficient as a proper nitrifying biofilter (higher flow/oxygen).


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## Quizcat (Dec 21, 2014)

Do you know the size difference of the individual pieces of Pond Matrix versus Matrix and De*Nitrate? I have both Matrix and De*Nitrate, and visually De*Nitrate pieces look to be only about 10% to 15% smaller in individual size. Just trying to get a sense of how Pond Matrix sizes up compared to the other two, and how the individual pieces of Pond Matrix would fit in the filter chamber.



WaterLife said:


> I only recommended pond matrix if you are using a higher flow rate. No harm in using it though, just not as space efficient.


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## Quizcat (Dec 21, 2014)

Seachem says Pond Matrix is about twice the size of regular Matrix...There seems to be such skepticism that the De*Nitrate media is inherently good for cultivating either bacteria that I'm having second thoughts about wasting time with it. I just figured I would try it since I already had a bag of it, and I wouldn't be out anything using it...hoping to get lucky I guess. 

The individual pieces of Pond Matrix are about twice the size of Matrix, but I calculate only needing about 300mL in the filter chamber for a 30 gallon tank, so I don't anticipate their being insufficient space for the Pond Matrix media to fit. Remember, I am not abandoning regular Matrix, it's in the Aquaclear 50 filter. 

I considered experimenting with Pond Matrix, or De*Nitrate to begin with, because I'm under the impression that regular Matrix is intended to cultivate *Aerobic* bacteria, which is great, but my focus is to cultivate *Anaerobic* bacteria. Am I mistaken about Matrix, that it's designed to mostly cultivate aerobic bacteria and not anaerobic bacteria?





Quizcat said:


> Do you know the size difference of the individual pieces of Pond Matrix versus Matrix and De*Nitrate? I have both Matrix and De*Nitrate, and visually De*Nitrate pieces look to be only about 10% to 15% smaller in individual size. Just trying to get a sense of how Pond Matrix sizes up compared to the other two, and how the individual pieces of Pond Matrix would fit in the filter chamber.


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## AbbeysDad (Apr 13, 2016)

Seachem claims that all of their pumice stone DeNitrate, Matrix, and Pond Matrix will culture both aerobic and anaerobic bacteria. The different recommended flow rates relative to the sizes is simply that anaerobic bacteria can only live in an environment of little/no oxygen. This is relative to the depth of the pores in the stone and the flow of the water passing through and around it. So in theory, anaerobic bacteria could exist with Pond Matrix with a faster water flow, while there would need to be a very slow flow for DeNitrate. Make sense?
Well that's the claim anyway. In theory, it is possible, just as it's possible with deep sand.
But as I keep saying and just my nickel, but I think you're better off focusing elsewhere.


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## Quizcat (Dec 21, 2014)

Don't worry, got the tracking on the sponge filter today. So, it'll be an integral part of the shotgun effect approach:grin2:



AbbeysDad said:


> Seachem claims that all of their pumice stone DeNitrate, Matrix, and Pond Matrix will culture both aerobic and anaerobic bacteria. The different recommended flow rates relative to the sizes is simply that anaerobic bacteria can only live in an environment of little/no oxygen. This is relative to the depth of the pores in the stone and the flow of the water passing through and around it. So in theory, anaerobic bacteria could exist with Pond Matrix with a faster water flow, while there would need to be a very slow flow for DeNitrate. Make sense?
> Well that's the claim anyway. In theory, it is possible, just as it's possible with deep sand.
> But as I keep saying and just my nickel, but I think you're better off focusing elsewhere.


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## AbbeysDad (Apr 13, 2016)

Quizcat said:


> Don't worry, got the tracking on the sponge filter today. So, it'll be an integral part of the shotgun effect approach:grin2:


Sponge filter?


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## Quizcat (Dec 21, 2014)

Ah, sorry, I think you suspected it might be my lighting, and recommended adding a bio-sponge. Well, somebody also recommended a sponge filter to fit over the intake. I think you're using a silica (pool filter) too, right? But, with my hard water here, I worry that I have a silica issue, which only feeds the brown algae. So, for now, I've decided to table that idea. But, I do want to try the bio-sponge idea. Is there a particular brand of bio-sponge that you've settled on? 

As for lighting, I have the Current Orbit Marine LED aquarium light, which has a ramp timer with an LED controller with wireless IR (infrared) remote, providing two independent light channels to program, blue and white LEDs. The LED light sits right on the top of the tank, which I've found to be very convenient and unobtrusive with respect to aesthetics. I have the model #4100, 18 Watts, 36 Dual Daylight/36 Dual Actinic LEDs, 72 LEDs Total. It has Dual Daylight and Dual Actinic multi-chip LEDs. It has a combination of 8,000K/12,000K white LEDs, along with 445nm/460nm actinic blue LEDs. 

So, it's actually meant for a marine tank, but I'm using it on my fresh water tank. I've adjusted the light intensity down to about 45% since it's not being used on a marine tank. I've played with it quite a bit, adjusting it down, thinking that the light intended for a marine tank might be dosing too much light on full intensity in a fresh water tank.

But, after all the experimentation I've done with this light, after also thinking that by dosing a marine light in a fresh water tank that my lighting was possibly the culprit responsible for the brown algae, I've concluded that it hasn't been the culprit. 

I don't have any plants in the tank, so no need to worry about nourishing plants. I am strictly interested in just the visual appearance of the tank right now. I could probably adjust this light down to 20% intensity, and be perfectly happy with the visual appearance. 

I am currently running it only about 5 hours a day these days, and the tank gets only ambient light during the daylight hours, and no direct sunlight from the windows during the day. I usually run the light from 6pm-11pm at night, so I can enjoy the fish while I also watch TV. So, the rest of the day the light is off, and the tank just gets ambient room light from the windows.

Maybe I'm wrong, and these marine LED "K" ranges are causing the problem, but I doubt it at their intensity, 45%, and for only five hours a day. But, if you think I should, I can turn it down even further, say 20% intensity, and I wouldn't really notice any visual difference. 



AbbeysDad said:


> Sponge filter?


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