New tank low nitrates to phosphate ratio

[vdubers]

New 7ft long 650 litre mixed reef running for a couple of months although I did use a mix of live rock from my old established system and new dry rock.

Things are going pretty well but currently going through the uglies with hair algea and cyano. But both of these are reducing.

My issue is I have an imbalance of nitrate to phosphate.

Nitrate detectable but either 1ppm or less (with salifert).

Phosphate 0.084 with Hanna ULR.

Alk 8.4-8.6 (fluctuates throughout the day)

1. Do I let the tank keep running as is since it’s still establishing its self?
2. Do I reduce the phosphate with phosgaurd that I have on hand?
3. Do I increase nitrate by potentially leaving filter socks in for longer or turning off skimmer during the day or both?
4. I could raise nitrate by dosing but figure if this is the route might as well try the free route first?

I don’t do water changes at the moment aiming for no water changes and using Xepta autoBalance to maintain Alk, calcium, magnesium and trace elements. However always plan to do water changes if nutrients get too high.

My few SPS frags are doing well and showing growth not sure how fast they are meant to grow but I’m taking any growth as a plus.

Pallys are not happy with some dying off Xenia also not happy but my organ pipe coral and clove polyps are loving life.

Fish for anyone interested
Regal tang
Foxface
Royal gramma
Copper band butterfly
Scopas tang (juvie)
Chromis x5
Pyjama cardinal (x3 juvie)
Flasher wrasse (juvie)
Fire fish x2
chalk basslet

Various CUC although I admit I could do with more.

Feed self collected mussel and nori in the morning. (Copperband goes crazy for mussel for anyone struggling to get theirs to eat, had mine for about 18 months now).

One cube frozen krill, one large cube frozen brine and marine fauna S pellets in the evening.

TLDR: new tank low nitrate to phosphate ratio. Do something or leave it?

Thanks for the help.

 

[Spare time]

I'd just dose something. If you have cyano, I'd probably not dose aminos or at least try it and stop if it gets worse. Otherwise, you can dose nitrate or ammonium chloride in tiny amounts. You can also leave the skimmer off during the day if you have one. I'd let the phosphate fall on its own. Do you have a refugium?

 

[Randy Holmes-Farley]

Forget the ratio. Nitrate is undesirably low regardless of the phosphate level (which, incidentally, is fine).

I’d either feed more or dose nitrate or ammonia.

 

[vdubers]

I'd just dose something. If you have cyano, I'd probably not dose aminos or at least try it and stop if it gets worse. Otherwise, you can dose nitrate or ammonium chloride in tiny amounts. You can also leave the skimmer off during the day if you have one. I'd let the phosphate fall on its own. Do you have a refugium?

Forget the ratio. Nitrate is undesirably low regardless of the phosphate level (which, incidentally, is fine).

I’d either feed more or dose nitrate or ammonia.

Thanks both for the replies. Seems the consensus is to leave phosphates, increase nitrates! I do have a refugium but it has a miniscule amount of Chaeto I am trying to get going. Think I might try feeding more and turning the skimmer off during the day for the rest of the week. Will test again at the weekend and if no change will sort out dosing nitrate.

I appreciate the help. After reading on here I did think this is the best action but wasn't sure with mine being a new system.

 

[jda]

If you are feeding all of those fish well, then there is little chance that you are nitrogen limited. Remember that nitrate is only one source of nitrogen and some corals cannot even use it and those that can use it have to spend energy converting it back to some other form like ammonium.

Feeding the fish more is usually the best thing to do if you think that you might be nitrogen deficient, but you likely are not. Growing corals is a sign that nothing is lacking for nitrogen.

 

[vdubers]

Update! I have been feeding more, turning skimmer off periodically and leaving the filter socks for longer and my nitrates today are around 5ppm

Phosphate however has also increased to 0.141.

The cyano is worse than ever.

Should I go back to my routine maintenance ( changing socks and leaving skimmer on) or something else?

Thanks

 

[ReefGeezer]

Feeding more and reducing export will increase nitrate but it can also increase dissolved organic carbon (DOC). That is likely the root cause of your Cyano. You might also identify the food(s) that are high in phosphate (likely the Nori and pellets) and feed less of them. I'd return to your previous protocol and then make small changes to it after the Cyano in under control.

IMO, there is no ideal number for nitrate and phosphate in the water column and certainly no golden ratio. I think that if they are both detectable, you have enough. The organisms that use the nutrients will use them in the ratio they need... not in the ratio that exists in the water column. Don't chase numbers.

 

[vdubers]

Feeding more and reducing export will increase nitrate but it can also increase dissolved organic carbon (DOC). That is likely the root cause of your Cyano. You might also identify the food(s) that are high in phosphate (likely the Nori and pellets) and feed less of them. I'd return to your previous protocol and then make small changes to it after the Cyano in under control.

IMO, there is no ideal number for nitrate and phosphate in the water column and certainly no golden ratio. I think that if they are both detectable, you have enough. The organisms that use the nutrients will use them in the ratio they need... not in the ratio that exists in the water column. Don't chase numbers.

Thanks happy to reduce Nori and stop pellets.

I’m guessing if DOC is the root cause of the Cyano the best way to reduce DOC would be water changes?

 

[ReefGeezer]

Thanks happy to reduce Nori and stop pellets.

I’m guessing if DOC is the root cause of the Cyano the best way to reduce DOC would be water changes?

Keeping your skimmer running is a good start. Extra GAC in a reactor can help lower the DOC quickly but may not be necessary. Water changes will reduce the levels of everything, including DOC, by the percentage you change.

I would simply cut back the feedings to your normal level and omit much of the Nori & pellets, make sure the skimmer is running all the time and skimming on the wetter side, and suck out the Cyano when doing water changes. Your tank looks pretty young. There will be more battles like this in the future.

 

[vdubers]

Keeping your skimmer running is a good start. Extra GAC in a reactor can help lower the DOC quickly but may not be necessary. Water changes will reduce the levels of everything, including DOC, by the percentage you change.

I would simply cut back the feedings to your normal level and omit much of the Nori & pellets, make sure the skimmer is running all the time and skimming on the wetter side, and suck out the Cyano when doing water changes. Your tank looks pretty young. There will be more battles like this in the future.

Thanks will give that a try. Yeah it is a young set up. I did have GHA then dinos then cyano in that order in my old tank but beyond syphoning them they cleared up with little intervention from me.