High Nitrate Issue

[JIsBusyReefing]

Hi all. I'm hoping someone here can help. For many months, I have been battling high nitrates without any success of remedying it. I've tried several things including the following but it never worked:

1. Large frequent water changes (made no difference)
2. Seachem Prime dosing (which worked for reducing no3 but tanked po4, fried my alveopora, and killed my chaeto)
3. Carbon dosing with sugar (melted my Xenia and stressed out my torch and frogspawn)
4. Reducing feeding (made no difference)
5. Cutting out foods with no phosphorus content (made no difference)
6. Biopellets (I'm at week 6 and it has made no difference at all)
7. Removing the refugium entirely thinking it was eating too much po4 (has made no difference so far)
8. MB7 dosing (has made no difference)
9. Vacuuming the sand bed and accumulated dutritus (made no difference)
10. Dosing Seachem Phosphorus daily at twice the recommended dose for my tank (made no difference at all to my phosphate level)

I have a 150 gallon tall tank (4' x 2' x 31") with a Pro Clear Aquatics model 300 sump, which has x3 filter socks and two compartments. In the large main compartment, I'm using a Reef Octopus Classic 200INT skimmer and a Red Starfish Media Reactor with 600mL of NPX biopellets then a MarinePure 8x8" plate in the second compartment. I feed one cube of frozen mysis twice daily and a small 4x4" sheet of nori once a day. Inhabitants include:

-A pair of Maroon Clowns
-Longnose Butterfly
-Juvenile Emperor Angel
-Flame Angel
-Coral Beauty Angel
-Blue Tang
-Sailfin Tang
-Powder Blue Tang
-Green Mandarin
-Cleaner Goby

Any ideas as to why my no3 is so high and why I can't get it down?

 

[Jekyl]

How high are your nitrates? Water changes always work except when your test kits are wrong.

 

[Jekyl]

Could probably cut the feeding in half also. I have 8 fish in my 90 and generally feed half a cube a day

 

[JIsBusyReefing]

How high are your nitrates? Water changes always work except when your test kits are wrong.

They are consistently around 40ppm. It does not budge. It's not the fault of the test either as I've had it tested using 3 different test kits which all show the same level.

 

[mdb_talon]

Share what your no3 numbers are that may help us help you.

A couple of things stand out. You say water changes make bo difference. They pretty much have to(at least in short term) if you using good water. This makes me wonder if your test kit is bad.

Other thing is if your phosphate is hitting zero then you gonna have hard time getting rid of nitrates. You say you are dosing double amount and it not going up...another indication tank is phosphate limited.

In any case if you can list po4/no3 values over time it may help figure out issue.

 

[JIsBusyReefing]

Could probably cut the feeding in half also. I have 8 fish in my 90 and generally feed half a cube a day

As stated in my OP, I already tried that for several weeks. It made no difference at all.

 

[Jekyl]

If your nitrates are at 40 today, what would they be in a week? How fast are they rising? Using RoDi? If at 40 and you do a 75% water change they will be at 10. If you can get them to an acceptable level, then maintaining it won't be as difficult as straight reduction without changing water.

 

[JIsBusyReefing]

Share what your no3 numbers are that may help us help you.

A couple of things stand out. You say water changes make bo difference. They pretty much have to(at least in short term) if you using good water. This makes me wonder if your test kit is bad.

Other thing is if your phosphate is hitting zero then you gonna have hard time getting rid of nitrates. You say you are dosing double amount and it not going up...another indication tank is phosphate limited.

In any case if you can list po4/no3 values over time it may help figure out issue.

~40ppm. It's not the test kit. I've had it tested using 3 different kits and they all show the same thing. My RO water shows nitrate at 0ppm, so it's not the water. I can't tell you the exact level of po4 because I only have API but it shows 0ppm po4 consistently despite the fact of the amount of phosphorus going into the tank. It will not go up.

 

[Jekyl]

Just RO water? Not RoDi? Beyond that making sure rocks are blown off during water changes (I use a turkey baister) and chaeto with a good light should take care of it.

 

[JIsBusyReefing]

If your nitrates are at 40 today, what would they be in a week? How fast are they rising? Using RoDi? If at 40 and you do a 75% water change they will be at 10. If you can get them to an acceptable level, then maintaining it won't be as difficult as straight reduction without changing water.

They don't rise or fall. They remain consistent around 40ppm. My corals aren't exactly thriving though and I'm trying to get that level down. I've already tried the large frequent water changes and no3 just goes right back up in a matter of a couple of days. It's too expensive to keep doing something that doesn't work. And yes, it's RODI. The water is clean and has no no3 in it.

 

[Jekyl]

They don't rise or fall. They remain consistent around 40ppm. My corals aren't exactly thriving though and I'm trying to get that level down. I've already tried the large frequent water changes and no3 just goes right back up in a matter of a couple of days. It's too expensive to keep doing something that doesn't work. And yes, it's RODI. The water is clean and has no no3 in it.

I asked because if just distilled water there could have been other things that would convert to nitrate after breaking down. Chaeto and a good light designed for it should take care of it. Bio media and marine blocks will work but if they are trapping detritus it could make things worse.

 

[JIsBusyReefing]

Just RO water? Not RoDi? Beyond that making sure rocks are blown off during water changes (I use a turkey baister) and chaeto with a good light should take care of it.

It's 4 stage aquatic life RODI system. The RODI water isn't the problem. I haven't tried blowing the live rock. You think it could be leeching no3 back into the water?

 

[JIsBusyReefing]

I asked because if just distilled water there could have been other things that would convert to nitrate after breaking down. Chaeto and a good light designed for it should take care of it. Bio media and marine blocks will work but if they are trapping detritus it could make things worse.

The block is newer. I doubt there's detritus in them. Especially with the filter socks protecting them from buildup.

 

[Jekyl]

Not leeching. Fish poop and old food gets trapped in all the crevices and breaks down into nitrate. When ever I do a 50% or bigger change I spend 20 minutes or so blasting my rocks and crevices from every angle to stir things up. Then change the water while vacuuming as much substrate as I can. After things settle and the water clears up I change any filter floss / socks that I have.

 

[Jekyl]

I also started with the same RoDi you have. I'd recommend switching to the BRS 5 stage. Built in TDS meter and more gallons per day.

 

[JIsBusyReefing]

Not leeching. Fish poop and old food gets trapped in all the crevices and breaks down into nitrate. When ever I do a 50% or bigger change I spend 20 minutes or so blasting my rocks and crevices from every angle to stir things up. Then change the water while vacuuming as much substrate as I can. After things settle and the water clears up I change any filter floss / socks that I have.

I'll give that a try for a few weeks and see what happens.

 

[Pistondog]

I'd restart the refugium, stay away from the seachem prime if it killed the chaeto. Use some reef roids until you can detect po4. Get a hanna po4 tester.
Nitrates don't bind to rock, but does get trapped in detritus.
This takes time. Maybe reduce feeding until you see the no3 dropping.

 

[Jekyl]

You'll be amazed at the clouds that come off your rocks from the turkey baister.

 

[sfin52]

40 isn't terribly high my nitrates are close to 100. I don't chase anymore. Fried my tank and ended with dino.
How often are you changing your socks?

 

[Pistondog]

40 isn't terribly high my nitrates are close to 100. I don't chase anymore. Fried my tank and ended with dino.
How often are you changing your socks?

Sox can be nitrate sources if not changes every 3 or 4 days.
Took mine out.