Nitrates just won't go down

[Jack Anastasia]

Hi all............I have a 300 gallon FOWLR and have been having problems with nitrates being at 100 or a little higher. I've cut way back on feeding, added a de-nitrator (AquaMaxx TS-3), have Seachem PhosGuard in bags, added a refugium, and did a 60 gallon water change 3 days ago and I can't get the nitrates down. Any ideas? Do I just keep doing more water changes?

Thanks for the help,

Jack

 

[PBnJOnWheat]

Hi all............I have a 300 gallon FOWLR and have been having problems with nitrates being at 100 or a little higher. I've cut way back on feeding, added a de-nitrator (AquaMaxx TS-3), have Seachem PhosGuard in bags, added a refugium, and did a 60 gallon water change 3 days ago and I can't get the nitrates down. Any ideas? Do I just keep doing more water changes?

Thanks for the help,

Jack

I’m not a fan of water changes honestly, but I’d get some MB7, or Dr.Tim’s and dose that to the instructions. Sounds like the tank needs some more bacterial breakdown. Keeping the redfield ratio ahas helped me personally 16:1 nitrates to phosphates in controlling algae. Anything growing in ur fuge?

 

[Jay Hemdal Verified Community Expert]

Welcome to Reef2Reef!

What test kit are you using? Does it report its measurement as nitrate or nitrate-nitrogen? Do you use filter socks or anything that can hold material while bacteria decomposes it?
Jay

 

[AirForestOne]

I was having the same issues a while back. I removed anything that could be holding decomposing things, filter on the return pump etc. That seemed to bring it down a little bit. I know I have a fish heavy tank so im also using a small amount of nopoX like others have suggested. I've also been doing 10-15% water changes every week but I was doing that to begin with so I haven't seen much change with that. I actually just ordered some filter socks to stick those on and see if I can catch anything that might be causing more problems than helping.

Starting slowly with the no pox seemed to help the most though. I have seen others that talk about other options for carbon dosing so that might be something to think about. How old is the tank?

 

[Rijodan]

Doesn't phosguard only control phosphate not nitrates? Think you'd be better with seachems purigen

 

[Jack Anastasia]

Thanks for all the great replies. I have chaeto growing in the refugium (size of a softball) along with more live rock. I have having an outbreak of red slime algae in the refugium and tank.......I assuming it's because of high nitrates. I'm using the Salifert Nitrate kit. I have filter pads on top of drip trays on the returns.....I change this each week. Yes to the phosguard, just wanted to list what I have running in my tank........also have carbon in a reactor and GFO in a reactor separate reactor running on this tank. Last, I have a skimmer and UV light.

 

[John08007]

I assume you have chaeto in the refugium? How long has it been running? It's not going to knock out nitrates overnight, chaeto growing?

 

[Timmtom49]

I have same size rank same issue same Equipment running on my tank its crazy I add gfo and carbon I notice my chest dieing out now tho but algea on back of display tank also is leaving

 

[moz71]

How long has the Denitrator been running? From my understanding this takes awhile to kick in. I put in a biopellet reactor (I know different) and it took about 8 weeks to start reducing nitrates

 

[Jack Anastasia]

Yes chaeto in refug for about 5 months now. Not really growing which is weird with all these nutrients available. De-nitrator has been running since April so should be working by now.

 

[John08007]

Thanks for all the great replies. I have chaeto growing in the refugium (size of a softball) along with more live rock. I have having an outbreak of red slime algae in the refugium and tank.......I assuming it's because of high nitrates. I'm using the Salifert Nitrate kit. I have filter pads on top of drip trays on the returns.....I change this each week. Yes to the phosguard, just wanted to list what I have running in my tank........also have carbon in a reactor and GFO in a reactor separate reactor running on this tank. Last, I have a skimmer and UV light.

Cyano is from phosphates, not nitrate. How often are you swapping out the gfo? Have you tested your phosphates?

 

[John08007]

I have same size rank same issue same Equipment running on my tank its crazy I add gfo and carbon I notice my chest dieing out now tho but algea on back of display tank also is leaving

What's your nitrates? I would bet that it's close to zero, chaeto requires nitrates to grow. Gfo will reduce phosphates, carbon will polish the water and remove toxins.

 

[John08007]

I have same size rank same issue same Equipment running on my tank its crazy I add gfo and carbon I notice my chest dieing out now tho but algea on back of display tank also is leaving

What's your nitrates? I would bet that it's close to zero, chaeto requires nitrates to grow. Gfo will reduce phosphates, carbon will polish the water and remove toxins

Yes chaeto in refug for about 5 months now. Not really growing which is weird with all these nutrients available. De-nitrator has been running since April so should be working by now.

You have 2 different filters removing nitrate. Its probably so low that there's not enough for the chaeto to flourish. What was the reason for adding the denitrator?

 

[Randy Holmes-Farley Verified Community Expert]

Hi all............I have a 300 gallon FOWLR and have been having problems with nitrates being at 100 or a little higher. I've cut way back on feeding, added a de-nitrator (AquaMaxx TS-3), have Seachem PhosGuard in bags, added a refugium, and did a 60 gallon water change 3 days ago and I can't get the nitrates down. Any ideas? Do I just keep doing more water changes?

Thanks for the help,

Jack

There are lots of good ways to lower nitrate, including organic carbon dosing.

If phosphate is too low, some nitrate control mechanisms (such as the chaetomorpha) may not work correctly. What is it?

 

[piranhaman00]

I am also having trouble with nitrate, planning a big sump cleaning and sand siphoning this weekend!

 

[vetteguy53081]

Try some chemipure elite
It reduces phosphate and nitrate and keeps it in check

 

[Jack Anastasia]

My nitrates are 100ppm or more and my phosphates are 0.1ppm. GFO was last changed on 10/16/20.

 

[excell007]

Last March my nitrate was >400, 15YO neglected fowlr, none of the test kits can read it without diluting the sample. I did three 30% WC every other day, then 25-30% weekly. In 8 weeks it's down to 10ppm. I also vacuum the sand in the sump and replace foam block with sock on the first water change. Phosphate is totally different issue, it's >4 last march, not it's still at .2, dosing LC. There's just too much phosphate on my live rocks.

 

[watchguy123]

I have found that siporax is a passive, seemingly safe and easy way to increase bacterial colonies and result in nitrate control. It takes 2-4 months to become sufficiently colonized

If your chaeto is not growing and you have appropriate lighting, eg. Kessil 160, then you may be lacking in iron and should consider an appropriate iron supplement.

I don’t consider the redfield ratio to be the best guide for nitrate to phosphate ratios in your tank water. It seems empirically that nitrate to phosphate has a large variation in ratio in many reef tanks and that anywhere from 10:1 to 200:1 is acceptable. I don’t know what the most ideal ratio is or even if one exists. Regardless, your ratio is 1000:1 and that sure seems high. When nutrients get out of the correct zone ( and to repeat, nobody is quite sure what that might be exactly although my previous suggestion is a workable zone) pests like cyano tend to proliferate.

Most people seem to try to keep nitrates somewhere between 1-10 ppm but there are those that like higher or lower numbers as well. Majority of opinion also seems to target phosphates below 0.3 but again there seems to be a much larger range above and below that number in reality.

 

[watchguy123]

I also should have added that the amount of food is critical in keeping balance with your nutrients. The import vs export mantra.

Everyone feeds different amounts and there is no right answer how much is enough vs too much. If you feed consistent amounts daily, then the obvious goal is to have physical removal ( sock filters, protein skimmers) and biological processes (siporax, live rock, chaeto, bacteria, sulfur denitrators, etc) remove excess nutrients. Ultimately finding a balance between well nourished fish and avoiding excessive nutrients