Nitrate reduction with Matrix

[GARRIGA]

Seachem Denitrate is a smaller matrix but requires a slower flow because of less interval pore structure yet because it’s smaller provides more surface area overall. That’s what I use in a modified undergravel filter since I can disk the flow down. Depending on the canister used, you might be able to reduce the flow which seems to be best around 50 gph. This is recommended by Seachem, is logical and seems to bear out based on my experiments.

As for placement, last would be prefer to ensure much of the detritus is trapped before hand. Because I’m using approximately 14 liters that’s not a concern. The detritus will decompose overtime and as it breaks down will make its way through the filter media yet there should be enough down flow that is void of any detritus. At least in theory.

I’d consider using carbon dosing along with the media as it’s more efficient when flow is higher than optimal. Nice part about the media is the lack of cloudiness one gets or how long it last. Just consider dosing at half recommended and adjusting based on how the water gets cloudy and how nitrates drop. This is most important when not using a protein skimmer to export the excess bacteria. Might also want to periodically dose heterotrophic bacteria although I’m not 100% convinced that’s needed since any excess will likely hibernate and multiple every 40 minutes once a good source made available. Doesn’t seem to hurt however.

 

[GARRIGA]

BTW, my experience with canister filters and denitrification is not cleaning them other than to remove filter floss and change carbon when water yellows. Decomposing detritus provides naturally the food needed in an anoxic environment needed to get heterotrophic bacteria to utilize nitrates. Why I’m not overly concerned with the internal structure of pumice (matrix) and more concerned with having surface area. Would do this with gravel but that’s 2.5 times heavier by volume and some of the interval surface area will be available within the pumice.

 

[Radicalrob1982]

Seachem Denitrate is a smaller matrix but requires a slower flow because of less interval pore structure yet because it’s smaller provides more surface area overall. That’s what I use in a modified undergravel filter since I can disk the flow down. Depending on the canister used, you might be able to reduce the flow which seems to be best around 50 gph. This is recommended by Seachem, is logical and seems to bear out based on my experiments.

As for placement, last would be prefer to ensure much of the detritus is trapped before hand. Because I’m using approximately 14 liters that’s not a concern. The detritus will decompose overtime and as it breaks down will make its way through the filter media yet there should be enough down flow that is void of any detritus. At least in theory.

I’d consider using carbon dosing along with the media as it’s more efficient when flow is higher than optimal. Nice part about the media is the lack of cloudiness one gets or how long it last. Just consider dosing at half recommended and adjusting based on how the water gets cloudy and how nitrates drop. This is most important when not using a protein skimmer to export the excess bacteria. Might also want to periodically dose heterotrophic bacteria although I’m not 100% convinced that’s needed since any excess will likely hibernate and multiple every 40 minutes once a good source made available. Doesn’t seem to hurt however.

I always wanted to try that stuff but was worrier about getting the right flow. Definitely beats buying a deinitrater for 400 dollars lol

 

[GARRIGA]

I always wanted to try that stuff but was worrier about getting the right flow. Definitely beats buying a deinitrater for 400 dollars lol

Test 20H working like a charm for far less than $400 lol

Still playing with flow to dial it in and hopefully soon move this experiment to a bigger build and incorporate what I learned.

 

[Reefer4fun]

I use canister filters filled with siporax for my nano tanks. The Eheim 2215 is able to keep zero nitrates on my WB25.

 

[TheXpander]

Honestly just fill the cannister with matrix. It works wonders if you maintain it and rinse it out in tank water. And obviously water changes will also help tremendously. Why are your nitrates so high? Have you checked your ro water before it's added ?

So ditch all the sponges and floss?

 

[Radicalrob1982]

All filter medias pretty well work the same. They have the holes deep inside that are somewhat anerobic and complete the de nitrating effect which helps keep nitrates down. Matrix does this because its very very porous. You could keep the floss and or sponges if you want. I prefer floss because of its great ability to filter water. Sponges work ok too if your constantly cleaning it like floss or they become a nitrate factory which doesn't help at all lol.

For example my 20 long reef. I have a sumpless system. I use a seachem tidal 75 hob filter and it works amazing. I just bought a large pack of Matrix and run filter floss in it. And I also have around 15 pounds of live rock with good flow throughout the tank. Honestly it takes forever for nitrates to rise. I mean months.

Myself I would run some floss on top where the water comes in and then run matrix throughout the rest. For the first while you'll have to maintain it quite frequently or the floss and media will become bung'd up quite fast as it sounds like you have a lot of nutrients in the water.

I also mentioned before I think, if you can afford it, I'd make sure to run a protein skimmer. No they're not the miracle solution but they sure help get rid of a lot of the proteins and stuff in the water before it has a chance to break down and cause issues with nitrates. They also make a big difference in film algae on the glass.

If water changes aren't helping, it may be that your source water has moderate to high nitrates already. I'd look into that as water changes are a huge help. And if your RO membranes are working properly you should have very little to no nitrates in the new water. Also test your water for ammonia. If its riddled with it, all it will do is fuel nitrites to make nitrates. I had this problem with an old freshwater tank. My nitrates were like around 50 and couldn't figure it out. I tested my new water and it had very little to no nitrates. Finally after months I was reading an article and decided to check my new water for ammonia. BAM lol. My new water was riddled with it. It was the sole reason my nitrates would go from 25 to 50 in a understocked tank in like a week. I was having to do 3 water changes a week to help keep my nitrates at around the 25 ppm mark. It was very frustrating.

Also Algone pads have helped me in the past with nitrate issues. They don't get rid of nitrates but they sure help in preventing them from rising. I also used nitrazorb which worked fairly well too.

So basically if feed your fish appropriately , have good clean water coming with no ammonia/nitrates, and filter with good media like matrix you should be able to get those nitrates down to a better level. It will be some work but its definitely fixable