Nitrates

[Treefer32]

I did my periodic 6 month testing of my aquarium. Everything is still where I expect it to be.
CA: 540
MG: 1440
Alk: 7.5dkh (Expect this to be around 8.5 reagent is 3 months old and nearing the bottom of the bottle.)
Salinity: 1.025
Nitrates: 23.2
Phosphates: .05

I raised my vodka dosing 1 ml per day for the past week. This lowered my phosphates from .08 to .05, but my nitrates remained the same.

Which tells me even with a margin of error, I could be nearing an imbalance between nitrates and phosphates. I had seen for many corals nitrates of between 5 and 10 are ideal and mine are over double that. I'm thinking of raising my vodka dosing another ml per day which would put me close to 10 ml per day on a 350 gallon system. My skimmer is producing great skimmate. So, I believe the export system is working. Plus my algae turf scrubber is producing bright green hair algae every 3-4 days.

Any suggestions on how to gain control of nitrates. Will dialing in vodka dosing further cause nitrate consuming bacteria to work more efficiently? Or will I bottom out phosphates and have a minimal reduction of nitrates?

 

[Reef.]

Wouldn’t doing that lower your po4 even more?
risk of dinos.

20 nitrates is not dangerous territory to be making big changes, many tanks run nitrates around 20.

unless you are having issues I would at most do a big water change and see how you go from there.

 

[homer1475]

Interesting as usually with carbon dosing, your nitrates reduce way faster then phosphates. But that also could mean your phosphate limited. Meaning not enough phosphates to lower the nitrates any further with carbon dosing.

What quite a few will do is continue with the carbon dosing, but dose phosphates so the bacteria can consume the nitrates further.

I also as above, would not worry about 20ppm nitrates. If they got any higher I would take action. But 20 is nothing to be too concerned with.

 

[Treefer32]

Thanks, I was thinking they're o.k. My Acros and Euphillia love the nitrates and phosphates. Going from phosphates of .08 to .05 in the last week has reduced my cyano bacteria so that was a big bonus. However, I have Zoas that melted within a week of putting them in the tank. I had gotten a nice rock of about 10 frags with 2-3 polyps on each frag plug. Half of the frag plug are completely empty. The other half might survive, I'm not sure. I was thinking maybe the nitrates as that's the only thing remotely wrong with my water chemistry. (I don't consider 20 'wrong' either.)

I'm not taking drastic measures that's for sure. I'll try slightly higher vodka dosing but outside of that. I'm going on 3 months of no water changes and phosphates and nitrates staying in the safe realm is a huge win for me of not doing water changes.

I am dosing Red Sea trace elements weekly at a ratio of 1:10 or 30 ml of trace elements per week. I really doubt trace elements would affect Zoas that much that they would die. I dipped them in coral RX when they started dying off for 10 minutes and all that came off was a ton of pods... I don't know if there's zoa eating pods? And a serpent star fish hidden under one of the frag plugs.

I'll make a minor tweak to vodka dosing, but, if next week the phosphates and nitrates are the same, I'll consider them limited by phosphates. I suppose I could feed reefroids, but ugg. I've seen what they can do when over dosed. If it's not broke, I'm not going to break it.