High nitrates undectable phosphates

[Matthias7]

My tank has high nitrates somewhere between 25-50 I use three different kits Red Sea, Nyos, and API. My phosphates are undectable using a salifert test. I am curently running a bare bottom tank roughly 320 gallons total. I have a light bio load and run biopellets (which I am removing). I do 20% water changes monthly. I do not run any kind of phosphate removal media. The tank looks good very little algae. I am considering doing nothing but regular maintenance. Why would my phosphates be so low? And would you do something more aggresive about the nitrates?

 

[atticus]

i have been fighting sort of the same prob. until i got the best advise i received from my LFS and it has worked for me. i was told to do a 50% WC which cut my nitrate from 50 (redsea test kit) to around 25ish waited 3 days did another 50% WC which dropped to 10 then waited a week another 50% and dropped to between 2 and 5. i then stopped feeding frozen everyday and went with pellets every other day and frozen sat and sun. this has kept me parameters down where i want them.

 

[jsker]

A thought, is that what ever algae you have is consuming the phosphate and giving a faults reading. For your nitrates, I would suggest running a bio media in your sump.

I use a ultra low phosphorus checker and I now finally know what my true phosphates are.

 

[Matthias7]

A thought, is that what ever algae you have is consuming the phosphate and giving a faults reading. For your nitrates, I would suggest running a bio media in your sump.

I use a ultra low phosphorus checker and I now finally know what my true phosphates are.

I'm sure there is algae consuming the phosphates but the imbalance is what is odd to me. I beleive it maybe related to not having substrate.

 

[jsker]

Like yourself I tried a few things, even biopellets. I have a sub straight, about 1 inch deep. Vacuumed, water changes, and after reconditions from fellow members like @120reefkeeper running a seeded bio-media really drops ones nitrates.

 

[SashimiTurtle]

I use a ultra low phosphorus checker and I now finally know what my true phosphates are.

I messed up and got the low range phosphate. Should have gotten the ULR Phosphorus. Red Sea will show 0.02ppm and the Hanna still says 0.

 

[Matthias7]

I built a sulfur denitrator because it target the nitrates and not phosphates I'm just nervous to fire it up since the tank looks good

 

[jsker]

I messed up and got the low range phosphate. Should have gotten the ULR Phosphorus. Red Sea will show 0.02ppm and the Hanna still says 0.

yes, the ULR phosphorus is the checker you need. @Hanna Instruments is really good with there costumer service, check and see if they will work with you.

 

[jsker]

I built a sulfur denitrator because it target the nitrates and not phosphates I'm just nervous to fire it up since the tank looks good

I was thinking of doing the same thing, but went with the bio media after a crash with bio pellets and did not want to mess with a reactor. I run life bio fil and a small amount of zeomix. One has to not use to much zeomix/zeovit or all the nitrates will be stripped to of the water.

 

[Matthias7]

Biopellets have really not done anything for me. Although I probably never used enough. I thought I could get away with minimal water changes since I had them running. Let's call it a failed experiment

 

[Randy Holmes-Farley Verified Community Expert]

It's possible the phosphate kit is not giving you accurate enough data, or the phosphate may actually be quite low, in which case some nitrate export mechanisms may not work well (such as the pellets).

If the tank looks good, I wouldn't agonize over nitrate values. However, watch carefully on removing the pellets as they may be doing more than you assume.

 

[SPSREEFS]

I would keep running the bio pellets and add more bio media or live rock.....................It will bring the nitrates down.

 

[Matthias7]

It's possible the phosphate kit is not giving you accurate enough data, or the phosphate may actually be quite low, in which case some nitrate export mechanisms may not work well (such as the pellets).

If the tank looks good, I wouldn't agonize over nitrate values. However, watch carefully on removing the pellets as they may be doing more than you assume.

I will test phosphates with a different kit today and see if I get similar results-- good idea thx I should done that already.
What do you think of sulfur denitrators? I do not mind water changes which I will continue to do but I don't think the answer long term. My other option is a refugium but if I confirm low phosphates I will be limited there- I don't think I want to dose phosphate.

 

[Matthias7]

I decided to continue my regular maintenance for now. I bought an ATI ICP test today. So I will wait until I get the results back before I take any action on the nitrates

 

[Reeferdood]

It's possible the phosphate kit is not giving you accurate enough data, or the phosphate may actually be quite low, in which case some nitrate export mechanisms may not work well (such as the pellets).

If the tank looks good, I wouldn't agonize over nitrate values. However, watch carefully on removing the pellets as they may be doing more than you assume.

Randy,
I have a friend that is dosing nopox and running GFO. His Phosphate is undetectable but the Nitrates are 50 ppm. What would you do to try to bring the nitrates down? Would you keep running GFO or take it offline and just do the carbon dosing??

 

[SashimiTurtle]

Randy,
I have a friend that is dosing nopox and running GFO. His Phosphate is undetectable but the Nitrates are 50 ppm. What would you do to try to bring the nitrates down? Would you keep running GFO or take it offline and just do the carbon dosing??

The GFO is keeping the PO4 down. Some activated carbon with the GFO should help to reduce the NO3. NOPOX will help to reduce NO3 also but can be a bit tricky to dial in.

 

[Randy Holmes-Farley Verified Community Expert]

Randy,
I have a friend that is dosing nopox and running GFO. His Phosphate is undetectable but the Nitrates are 50 ppm. What would you do to try to bring the nitrates down? Would you keep running GFO or take it offline and just do the carbon dosing??

Yes, stop or reduce the GFO.

Might also need an uptick in NOPOX, but I'd do that if needed after the phosphate rises a bit and we have a chance to see if increased phosphate allowed more nitrate export.

 

[Reeferdood]

Yes, stop or reduce the GFO.

Might also need an uptick in NOPOX, but I'd do that if needed after the phosphate rises a bit and we have a chance to see if increased phosphate allowed more nitrate export.

Thank you sir, always value your input.. I have another question about my system and a Ca Rx that I just installed but Ill post that in another thread....

 

[Randy Holmes-Farley Verified Community Expert]

Thank you sir, always value your input.. I have another question about my system and a Ca Rx that I just installed but Ill post that in another thread....

You're welcome.

Happy Reefing.