Coral issues due to Nutrients?

[schuby]

My opinion is that your phosphate is too low and your SPS are starving to death. A safer, minimum level of phosphate is 0.1 ppm. If you had a mature tank with high import and high export, then running at your near-zero level may be fine.

My other opinion is that we should keep at least 1-2ppm of nitrate in our tanks. It has been suggested on here that this minimum level prevents the creation of sulfide gas (toxic to fish and us).

FWIW, my target levels are 0.15-0.25 ppm phosphate and 15-25ppm of nitrate. I have a mixed reef with mostly SPS and a few LPS. I've only ever lost SPS (after having them for more than 2 weeks) from too low level of nutrients. I've never lost SPS by feeding/dosing too much (high nutrients). My current tank is just over two years old.

 

[arking_mark]

My opinion is that your phosphate is too low and your SPS are starving to death. A safer, minimum level of phosphate is 0.1 ppm. If you had a mature tank with high import and high export, then running at your near-zero level may be fine.

My other opinion is that we should keep at least 1-2ppm of nitrate in our tanks. It has been suggested on here that this minimum level prevents the creation of sulfide gas (toxic to fish and us).

FWIW, my target levels are 0.15-0.25 ppm phosphate and 15-25ppm of nitrate. I have a mixed reef with mostly SPS and a few LPS. I've only ever lost SPS (after having them for more than 2 weeks) from too low level of nutrients. I've never lost SPS by feeding/dosing too much (high nutrients). My current tank is just over two years old.

I think you may be correct.

 

[arking_mark]

Just a quick update. My phosphates are still low at 0.02ppm and nitrates just don't move.

As remaining corals seem to be ok, I'm not as concerned.

 

[arking_mark]

Ok. So I stopped carbon dosing for a week (Nyos Zero) to see what the impact would be. My PO4 is up to 0.07 (probably due to heavier feeding), and my Nitrate seems to be 20ppm, which is slightly lower than the normal 25ppm...but within testing error.

Corals may be a little better.

The expensive corals that I moved from my old tank:
- Jellybean Chalice - never had an issue and is beautiful and growing
- WD Tenius - never really had an issue and is slightly less puffy but has grown. Still a small frag and never had color.
- Kung pow - browned out and died
- Hallucination Zoas - shrunk to nothing and never open
- Jawbreaker Mushroom - Lost the mother, but have 2 babies that seem to be doing well
- SR Crazy Bounce Mushroom - doing great

Other coral I moved from my old tank:
- Grandi Palys - Doing great
- Utter Chaos - Open, but look like crap
- Rasta - finally coming around
- Mandarin Orange Zoa - barely opening, but alive
- Vampires in Drag - not looking great
- ASD - All but gone
- Ultra Yuma - gone
- 2 unidentified shrooms - coming back and now starting to color up

New additions have not done well:
- Pink Floyd mini colony - dead
- Bubble Gum Digi mini colony - browned out maybe half dead maybe half coming back
- Fireworks Polyps #1 - all but dead
- Fireworks Polyps #2 - not great
- Sunset Monti - bleached, may be dying
- Forest Fire Digi - ok
- Green Slimer - ok
- Paletta Pink Tip - browned out
- Blue Poki - not blue anymore

-

 

[Shirak]

What did you do for rock in the new tank? Guessing old rock and added new rock? Was the new dry?

 

[arking_mark]

What did you do for rock in the new tank? Guessing old rock and added new rock? Was the new dry?

Started with everything new. Just added pieces after tank cycled and fish were thriving.

 

[Shirak]

Could be your rock is absorbing phosphates still.

 

[arking_mark]

So It's been about 2 weeks of no carbon dosing and pH is still bouncing off 0...but my nitrates are finally coming down as I hit 15ppm today. The refugium seems to be kicking in and growing more stuff...GHA is taking over, but chaeto is growing.

I sort of feel the carbon dosing inhibited the refugium and prevented nitrates from lowering. I don't think it had any effect on PO4.

 

[Shirak]

So It's been about 2 weeks of no carbon dosing and pH is still bouncing off 0...but my nitrates are finally coming down as I hit 15ppm today. The refugium seems to be kicking in and growing more stuff...GHA is taking over, but chaeto is growing.

I sort of feel the carbon dosing inhibited the refugium and prevented nitrates from lowering. I don't think it had any effect on PO4.

Sorry I don't have any experience with carbon dosing so can't help on that. Have your phosphates stayed around .05 now? With some phosphates in the water the macro and micro algae will kick in and help take down nitrate. You may need to add some CUC to help with hair algae etc in the tank... it's always such a balancing act!

How are the corals looking now?

 

[arking_mark]

Sorry I don't have any experience with carbon dosing so can't help on that. Have your phosphates stayed around .05 now? With some phosphates in the water the macro and micro algae will kick in and help take down nitrate. You may need to add some CUC to help with hair algae etc in the tank... it's always such a balancing act!

How are the corals looking now?

Corals seem status quo.

No GHA in DT, only in refugium.

 

[Shirak]

Corals seem status quo.

No GHA in DT, only in refugium.

Ah ok well that's a good thing. Any CUC in the refugium? I put some turbos and astrea and a few hermits in mine to help keep the micro algae down.

 

[Randy Holmes-Farley]

My opinion is that your phosphate is too low and your SPS are starving to death. A safer, minimum level of phosphate is 0.1 ppm. If you had a mature tank with high import and high export, then running at your near-zero level may be fine.

My other opinion is that we should keep at least 1-2ppm of nitrate in our tanks. It has been suggested on here that this minimum level prevents the creation of sulfide gas (toxic to fish and us).

FWIW, my target levels are 0.15-0.25 ppm phosphate and 15-25ppm of nitrate. I have a mixed reef with mostly SPS and a few LPS. I've only ever lost SPS (after having them for more than 2 weeks) from too low level of nutrients. I've never lost SPS by feeding/dosing too much (high nutrients). My current tank is just over two years old.

IMO, that "safe minimum" seems quite high. Plenty of great tanks have much lower levels of phosphate. I'd personally put the minimum closer to 0.02 ppm, or maybe even lower, but it may depend on how much particulate food your corals get.

I also don't believe that low nitrate leads to H2S problems, but I do agree that corals need a good source of N, and nitrate at 2-10 ppm is an acceptable way to do it.

 

[schuby]

IMO, that "safe minimum" seems quite high. Plenty of great tanks have much lower levels of phosphate. I'd personally put the minimum closer to 0.02 ppm, or maybe even lower, but it may depend on how much particulate food your corals get.

I also don't believe that low nitrate leads to H2S problems, but I do agree that corals need a good source of N, and nitrate at 2-10 ppm is an acceptable way to do it.

Randy, I've shared my opinions for an SPS tank. I try to always stay away from absolutes on here. A long-term, expert reefer may be able to maintain SPS with 0.02ppm residual of phosphate, but mere mortals like myself would likely fail.

The H2S reference is based on a post from @Lasse : something along the line that Nitrate can prevent H2S from being formed by anaerobic bacteria and it is safer for us reefers to keep some Nitrate instead of zero. He's much more educated and expert than me. I don't understand the chemistry, but I choose to have confidence in his recommendations.

Thank you, again, for all your posts on here. Many of us are very grateful.

 

[Randy Holmes-Farley]

Randy, I've shared my opinions for an SPS tank. I try to always stay away from absolutes on here. A long-term, expert reefer may be able to maintain SPS with 0.02ppm residual of phosphate, but mere mortals like myself would likely fail.

The H2S reference is based on a post from @Lasse : something along the line that Nitrate can prevent H2S from being formed by anaerobic bacteria and it is safer for us reefers to keep some Nitrate instead of zero. He's much more educated and expert than me. I don't understand the chemistry, but I choose to have confidence in his recommendations.

Thank you, again, for all your posts on here. Many of us are very grateful.

I don't disagree that having nitrate in a low O2 environment will slow or "prevent" the production of H2S because the nitrate will be consumed first, before H2S is formed. O2 does the same thing even before nitrate is consumed.

But I don't see a relationship between nitrate in the water column and the potential for hydrogen sulfide deep in sand beds or rock pores where H2S may form. By extension, this idea would claim that having O2 in the water (which is always there) prevents the production of hydrogen sulfide, and that assertion fails for the same reason.

 

[arking_mark]

IMO, that "safe minimum" seems quite high. Plenty of great tanks have much lower levels of phosphate. I'd personally put the minimum closer to 0.02 ppm, or maybe even lower, but it may depend on how much particulate food your corals get.

I also don't believe that low nitrate leads to H2S problems, but I do agree that corals need a good source of N, and nitrate at 2-10 ppm is an acceptable way to do it.

So I don't think I'm worried about PO4. Tank is being fed and some days I have had readings as high as 0.09ppm. PO4 seems to be very transient in my system.

My concern has been NO3 being stuck at 25ppm. This might not even be the problem...just eliminating possible cause for why new corals haven't done so well in my tank.

Coincidence or not, stopping carbon dosing correlated with my refugium starting to do produce better which I believe has reduced my nitrates.

 

[Randy Holmes-Farley]

So I don't think I'm worried about PO4. Tank is being fed and some days I have had readings as high as 0.09ppm. PO4 seems to be very transient in my system.

My concern has been NO3 being stuck at 25ppm. This might not even be the problem...just eliminating possible cause for why new corals haven't done so well in my tank.

Coincidence or not, stopping carbon dosing correlated with my refugium starting to do produce better which I believe has reduced my nitrates.

FWIW, bacteria and macroalgae do not just fight for N and P, they also need a host of trace elements. Even with adequate N and P, maybe stopping the organic dosing has allowed something else to rise again.

That said, I grew macroalgae and dosed vinegar together without apparent issue. At very high vinegar doses, I think the macroalgae even grew better (meaning worse, since it was caulerpa and was also growing in my main tank) for reasons I am not sure of.

 

[Lasse]

I also don't believe that low nitrate leads to H2S problems

I don't disagree that having nitrate in a low O2 environment will slow or "prevent" the production of H2S because the nitrate will be consumed first, before H2S is formed. O2 does the same thing even before nitrate is consumed.

As you say in the second statement - this is a well known fact among people used of sewage treatment. There is a lot of publication that have shown that nitrates around 2-3 ppm hinder H2S forming during anaerobic conditions. NO3 is easier to use in anaerobic metabolism - therefor it will favour those bacteria that are able to use NO3 as a electron acceptor. If NO3 levels is to low - it favour those microorganisms that use different sulphur compounds as electron acceptors,

IME if you have NO3 in the water column - it will penetrate a part of the sandbed - at least this is the idea behind the denitrification theories of DSB and the jaubert system and also the denitrification theories in porous rocks, For me it is also a risk that part of the water column (below stones) get oxygen free and possible H2S2 production zones will be created - NO3 will hinder that. In very dense coral systems (as in very well planted fresh water aquariums) will the cell respiration during night (no photosynthetic oxygen production) consume as much oxygen that - at least in skimmer free aquariums - that lower parts (and parts with low circulation) can be oxygen free. If there is NO3 in the water (not consumed by the aerobic cell respiration of corals, fish or plants in fresh water ) it will hinder H2S2 production in those events - H2S2 that by itself will be chemical oxidised and further diminish the oxygen level in in the water column. In step - first we take the oxygen - then we take the NO3 and finally we go for the sulphur compounds

I also think that is logical somersault to believe that oxygen will not penetrate into the sandbed. It will BUT it will be consumed by aerobic bacteria in the sandbed - NO3 will also be consumed (also from the water column) but first after the oxygen is consumed - it penetrate deeper than the oxygen - IMO - and first after i NO3 have been consumed - the H2S2 producer will be able to work. It is not either total true that the water always will be oxygenrich. If you stop the oxygen production from the photosynthesis and the diffusion of oxygen from the air - normal bacterial activity (plus the fish and the cell metabolism from other aerobic organisms) will consume all oxygen from the water. In order to withhold the oxygen in a biological active water system you need to put in the consumed oxygen again. For me - its the same with NO3.

I have rather many times - in system with at least 2 mg/L NO3 - dug out DSB without any H2S2 anywhere in the sandbed. You will not miss if it is H2S2 in a DSB when you dug out it.

Sincerely Lasse

 

[arking_mark]

FWIW, bacteria and macroalgae do not just fight for N and P, they also need a host of trace elements. Even with adequate N and P, maybe stopping the organic dosing has allowed something else to rise again.

That said, I grew macroalgae and dosed vinegar together without apparent issue. At very high vinegar doses, I think the macroalgae even grew better (meaning worse, since it was caulerpa and was also growing in my main tank) for reasons I am not sure of.

I've was dosing ChaetoGro when the refugium wasn't productive.

 

[Randy Holmes-Farley]

As you say in the second statement - this is a well known fact among people used of sewage treatment. There is a lot of publication that have shown that nitrates around 2-3 ppm hinder H2S forming during anaerobic conditions. NO3 is easier to use in anaerobic metabolism - therefor it will favour those bacteria that are able to use NO3 as a electron acceptor. If NO3 levels is to low - it favour those microorganisms that use different sulphur compounds as electron acceptors,

IME if you have NO3 in the water column - it will penetrate a part of the sandbed - at least this is the idea behind the denitrification theories of DSB and the jaubert system and also the denitrification theories in porous rocks, For me it is also a risk that part of the water column (below stones) get oxygen free and possible H2S2 production zones will be created - NO3 will hinder that. In very dense coral systems (as in very well planted fresh water aquariums) will the cell respiration during night (no photosynthetic oxygen production) consume as much oxygen that - at least in skimmer free aquariums - that lower parts (and parts with low circulation) can be oxygen free. If there is NO3 in the water (not consumed by the aerobic cell respiration of corals, fish or plants in fresh water ) it will hinder H2S2 production in those events - H2S2 that by itself will be chemical oxidised and further diminish the oxygen level in in the water column. In step - first we take the oxygen - then we take the NO3 and finally we go for the sulphur compounds

I also think that is logical somersault to believe that oxygen will not penetrate into the sandbed. It will BUT it will be consumed by aerobic bacteria in the sandbed - NO3 will also be consumed (also from the water column) but first after the oxygen is consumed - it penetrate deeper than the oxygen - IMO - and first after i NO3 have been consumed - the H2S2 producer will be able to work. It is not either total true that the water always will be oxygenrich. If you stop the oxygen production from the photosynthesis and the diffusion of oxygen from the air - normal bacterial activity (plus the fish and the cell metabolism from other aerobic organisms) will consume all oxygen from the water. In order to withhold the oxygen in a biological active water system you need to put in the consumed oxygen again. For me - its the same with NO3.

I have rather many times - in system with at least 2 mg/L NO3 - dug out DSB without any H2S2 anywhere in the sandbed. You will not miss if it is H2S2 in a DSB when you dug out it.

Sincerely Lasse

IMO, suggesting that nitrate will prevent hydrogen sulfide issues (or conversely, that zero nitrate will cause them) is exactly like claiming that higher alkalinity will prevent low pH or that low alkalinity causes it.

Higher alkalinity will give a greater tendency to higher pH (just as more nitrate gives a slightly bigger buffer before H2S might be formed), but lower alkalinity does not cause low pH, and high alkalinity does not prevent it (just as low nitrate does not cause hydrogen sulfide, and high nitrate does not prevent it).

 

[Randy Holmes-Farley]

I've was dosing ChaetoGro when the refugium wasn't productive.

Well, hard to say what caused your issues.