0 nitrate, high(ish) phosphate, GHA, CUC problems

[lmfbs]

Parameters:
96g
Nitrate: 0.0 (Hanna HR)
Phos: 0.31 (Hanna ULR)
kH: 8.96 (reefkeeper)
Heating set with inkbird, no fluctuations or anything.

This tank has previously had very high nitrates (100+) but resolved this through automated WCs, carbon dosing and time. Nitrates have been running between 5 - 20 for about 6 months.

Inhabitants:
Foxface
Scopas Tang
Fairy wrasse
2 x clowns
Lepoard wrasse

Previously, I have had snails and 2 chocolate zebra starfish. The snails all died (I assume from dinos) and a few months back, the starfish also died. I have no idea what caused the stars to die - they were otherwise healthy and I had them for about 3 years, but they were at least 7 years old when I got them.

After they died, I tested for copper using a Salfert test, and I have also tested again a few times - no signs. I've never used copper in the tank, but, better safe than sorry.

I've been trying to buy more snails, but I haven't been able to buy any for months. I have 6 turbos on their way to me (I live in NZ and CUC is difficult to come by, and really limits my options).

I have softies and zoas which are growing well. I've never had success keeping SPS, and I'm a bit nervous about spending a bunch of money on corals when the tank is feeling unstable.

The problem
I have GHA, have previously struggled with dinos, and I'm seeing the dinos coming back. I assume this is from low nitrates.

I've been manually removing GHA, using filter socks which I'm changing every 2 days, and wet skimming. I have an algae scrubber, but the tank grows algae quicker than the scrubber right now. The fish aren't very interested in eating the GHA, though sometimes they will pick at it. Maybe I feed them too much?

I'm trying to compensate for the CUC to avoid algae and dinos by keeping the lights low, and doing frequent blackouts, but obviously, I'd rather have the lights on.

What should I do first?

 

[strich]

Dinos thrive in environments where nitrate is zeroed out because it starves their competitors (beneficial microalgae, diatoms, etc).
You need to get those nitrate numbers up - Probably stop the carbon dosing asap. Look into dosing nitrates, or maybe feeding the fish more if you've been going light on that. Stop skimming all the neutriants out and get those lights back up to a normal schedule IMO.
Once the nitrate / phos ratio is balanced, hopefully you'll get a dirty phase where diatoms and film algae explode. Embrace that - it means the tank is healing and the diatoms are outcompeting the dinos.

I think you might want to not put those incoming CUC in there until the dinos are gone - They're toxic to them, and the fish which is why they aren't eating the GHA.

 

[lmfbs]

Dinos thrive in environments where nitrate is zeroed out because it starves their competitors (beneficial microalgae, diatoms, etc).
You need to get those nitrate numbers up - Probably stop the carbon dosing asap. Look into dosing nitrates, or maybe feeding the fish more if you've been going light on that. Stop skimming all the neutriants out and get those lights back up to a normal schedule IMO.
Once the nitrate / phos ratio is balanced, hopefully you'll get a dirty phase where diatoms and film algae explode. Embrace that - it means the tank is healing and the diatoms are outcompeting the dinos.

I think you might want to not put those incoming CUC in there until the dinos are gone - They're toxic to them, and the fish which is why they aren't eating the GHA.

I haven't been carbon dosing for a few months because the nitrates have been looking where I want them. Might look into UV - I didn't use it last time when I had dinos but this time they disappear into the water column at night so it's more feasible. Really need to get out my microscope to ID them.

Interestingly, last time I had dinos, my nitrates were up over 100, so this feels like a different fight!

I'll pop the snails into a QT when they arrive next week and start dosing nitrates

 

[sixty_reefer]

Dinoflagellate mats can proliferate across a range of environmental conditions, including systems characterised by elevated concentrations of dissolved organic matter as well as those in which nitrogen or phosphate availability has become limiting, the trick to avoiding them is finding a balance.

 

[Subsea]

Dinos thrive in environments where nitrate is zeroed out because it starves their competitors (beneficial microalgae, diatoms, etc).
You need to get those nitrate numbers up - Probably stop the carbon dosing asap. Look into dosing nitrates, or maybe feeding the fish more if you've been going light on that. Stop skimming all the neutriants out and get those lights back up to a normal schedule IMO.
Once the nitrate / phos ratio is balanced, hopefully you'll get a dirty phase where diatoms and film algae explode. Embrace that - it means the tank is healing and the diatoms are outcompeting the dinos.

I think you might want to not put those incoming CUC in there until the dinos are gone - They're toxic to them, and the fish which is why they aren't eating the GHA.

Kudoes to your post with one exception; there is no ideal fixed ratio between inorganic nitrate & phosphate, It is only necessary to have some nitrogen and some phosphate. POC (Particulate Organic Carbon) & DOC (Dissolved Organic Carbon) can contain those nutrients.

 

[CHSUB]

Stop testing no3 if it is going to cause you to react, if stuff is growing there is no nitrogen deficiency. Continue removing nuisance algae manually add corals to limit space. You are going the right way with maintenance just continue.

. I assume this is from low nitrates.

This is just false. Stop doing black outs and improve your maintenance.

 

[Mr. Mojo Rising]

Can we have a picture and a description of your filtration, how much do you feed? Having nitrates go up over 100, then down to zero but sounds like you have a baf algae problem, which will skew the test results, so in this case a picture is very helpful to see what is going on.

 

[Subsea]

Parameters:
96g
Nitrate: 0.0 (Hanna HR)
Phos: 0.31 (Hanna ULR)
kH: 8.96 (reefkeeper)
Heating set with inkbird, no fluctuations or anything.

This tank has previously had very high nitrates (100+) but resolved this through automated WCs, carbon dosing and time. Nitrates have been running between 5 - 20 for about 6 months.

Inhabitants:
Foxface
Scopas Tang
Fairy wrasse
2 x clowns
Lepoard wrasse

Previously, I have had snails and 2 chocolate zebra starfish. The snails all died (I assume from dinos) and a few months back, the starfish also died. I have no idea what caused the stars to die - they were otherwise healthy and I had them for about 3 years, but they were at least 7 years old when I got them.

After they died, I tested for copper using a Salfert test, and I have also tested again a few times - no signs. I've never used copper in the tank, but, better safe than sorry.

I've been trying to buy more snails, but I haven't been able to buy any for months. I have 6 turbos on their way to me (I live in NZ and CUC is difficult to come by, and really limits my options).

I have softies and zoas which are growing well. I've never had success keeping SPS, and I'm a bit nervous about spending a bunch of money on corals when the tank is feeling unstable.

The problem
I have GHA, have previously struggled with dinos, and I'm seeing the dinos coming back. I assume this is from low nitrates.

I've been manually removing GHA, using filter socks which I'm changing every 2 days, and wet skimming. I have an algae scrubber, but the tank grows algae quicker than the scrubber right now. The fish aren't very interested in eating the GHA, though sometimes they will pick at it. Maybe I feed them too much?

I'm trying to compensate for the CUC to avoid algae and dinos by keeping the lights low, and doing frequent blackouts, but obviously, I'd rather have the lights on.

What should I do first?

I would optimize algae scrubber operation and get more CUC for GHA. Can you better describe your algae scrubber’s performance?

 

[lmfbs]

Can we have a picture and a description of your filtration, how much do you feed? Having nitrates go up over 100, then down to zero but sounds like you have a baf algae problem, which will skew the test results, so in this case a picture is very helpful to see what is going on.

I use 225 micron mesh filter socks which I change every second day, and I have an Octo elite 200-int skimmer. Skim isn't super wet. The tank is a waterbox 130.4 (480l system volume). I've set up the top-off area as a refugium with LR rubble and I have a trickle down DIY algae skimmer.

I feed daily, usually 1/4 to 1/2 of a cube of brine, mysis, occasionally bloodworms, or the equivalent in various pellets. If I'm feeding pellets, it's generally aquaforest but I do have a bit of a variety. I feed nori 5 days a week usually - they get about 1/4 of a sheet, then more if they eat quick. Sometimes, instead of nori I feed spiralina flakes, or those algae wafers - my scopas in particular really loves them.

I do think there's a chance the nitrate situation is because the algae is sucking the nutrients out of the water. In saying that, it took months and months to bring my nitrates down and it was a pretty gradual drop.

 

[Subsea]

Stop testing no3 if it is going to cause you to react, if stuff is growing there is no nitrogen deficiency. Continue removing nuisance algae manually add corals to limit space. You are going the right way with maintenance just continue.


This is just false. Stop doing black outs and improve your maintenance.

You & I will not agree on this because it’s more complicated than just inorganic nitrate.

“Zero nitrates do not directly create dinoflagellates, but they create the perfect, sterile conditions for a bloom. Dinoflagellates exist in virtually every saltwater aquarium, but they are normally suppressed and kept in check by a diverse microbiome”

“Dinoflagellates' Adaptability: Dinoflagellates are incredibly opportunistic. They can survive and thrive in ultra-low nutrient environments far better than other organisms, allowing them to rapidly multiply and take over without facing any natural competition.“

 

[lmfbs]

I would optimize algae scrubber operation and get more CUC for GHA. Can you better describe your algae scrubber’s performance?

The algae scrubber is definitely not as efficient as I'd like it - it grows quite a bit of slime along with GHA.

This is 6 days of growth. The blob at the top that sort of looks like cyano is actually GHA, it just looks weirdly shiny in the pic.

One of my major problems, as I mentioned in my OP is that CUC is simply not very available here. I've been waiting literally months for more snails, and even with a special order was only able to get 6. We don't have hermits or any types of crabs. We get turbo snails, occasionally astreas (I haven't seen any for sale in the country in about 2 years), starfish, some types of shrimp and long spine urchins.

 

[Subsea]

The algae scrubber is definitely not as efficient as I'd like it - it grows quite a bit of slime along with GHA.

This is 6 days of growth. The blob at the top that sort of looks like cyano is actually GHA, it just looks weirdly shiny in the pic.

One of my major problems, as I mentioned in my OP is that CUC is simply not very available here. I've been waiting literally months for more snails, and even with a special order was only able to get 6. We don't have hermits or any types of crabs. We get turbo snails, occasionally astreas (I haven't seen any for sale in the country in about 2 years), starfish, some types of shrimp and long spine urchins.

That doesn’t look like much growth in 6 days for ATS. MAYBE increase light intensity or duration.

PS: When nitrates were elevated was ATS algae growth more robust?

 

[strich]

That doesn’t look like much growth in 6 days for ATS. MAYBE increase light intensity or duration.

Maybe not surprising if there are is no nitrate availability?

I also have a Waterbox 130.4 - Cool to see another one in the wild. Would love to see a few whole tank shots, and as someone else mentioned it can help people give you better advice.

 

[BeanAnimal]

Once the nitrate / phos ratio is balanced,

This is a misconception rampantly repeated on this hobby.


The ratio of N and P in the water column does not drive what organisms use. The level of each should be viewed independently and kept within reasonable ranges, regardless of their ratio to one another.

 

[BeanAnimal]

Dinoflagellate mats can proliferate across a range of environmental conditions, including systems characterised by elevated concentrations of dissolved organic matter as well as those in which nitrogen or phosphate availability has become limiting, the trick to avoiding them is finding a balance.

Balance of what exactly?

They can happen anywhere, avoid them with balance.

It is abstract and covers all outcomes.

 

[BryanM]

Your ATS isn't working IMO. As subsea said increase light or duration, or both.

This is my ATS, when I failed to harvest for two weeks, it has two screens that are roughly the same size as yours.

 

[strich]

This is a misconception rampantly repeated on this hobby.


The ratio of N and P in the water column does not drive what organisms use. The level of each should be viewed independently and kept within reasonable ranges, regardless of their ratio to one another.

Agreed. 'Balanced' was probably the wrong word there. The main goal is just making sure both N and P are independently kept in a healthy, detectable range so biological limitation doesn't hand the tank over to dinos. Which is also what the other poster was referring to as well. While the precise chemistry terminology matters, in practical terms for the OP, the advice remains the same: get those numbers off zero.

 

[sixty_reefer]

Balance of what exactly?

They can happen anywhere, avoid them with balance.

It is abstract and covers all outcomes.

I was referring to the relative availability of dissolved organic matter, nitrogen and phosphorus. Considering the sentence explicitly mentions elevated organics and nitrogen or phosphorus limitation, I thought that was reasonably clear from the context and should require little guesswork to interpret.

 

[BeanAnimal]

Agreed. 'Balanced' was probably the wrong word there. The main goal is just making sure both N and P are independently kept in a healthy, detectable range

Exactly!

in practical terms for the OP, the advice remains the same: get those numbers off zero.

True zero is probably rarer than test results suggest. Food goes in, fish produce waste, so a zero reading is a snapshot between inputs and consumption. We don't know if that is actually a problem or not. But, all of that said, I would agree that getting the testable number above zero offers a hedge that it can't be true zero.

I was referring to the relative availability of dissolved organic matter, nitrogen and phosphorus. Considering the sentence explicitly mentions elevated organics and nitrogen or phosphorus limitation, I thought that was reasonably clear from the context and should require little guesswork to interpret.

You said dinos occur in high organic systems and in nitrogen or phosphorus limited systems. That covers all tanks. Restating those variables doesn't offer clarity or make anything obvious. I asked what that balance point was.

What condition prevents dinos? How does one measure and change the "balance" of the system to what target?

The original statement still covers all outcomes and explains none of them. Advising someone to find balance between variables you just said produce dinos at both extremes and every point in between is not advice, an explanation or obvious.

You just restated what you said and called it clarification without answering the questions. That is circular.

 

[CHSUB]

sterile conditions

My disagreement is aquariums will never be sterile, just the dust in typical homes produce nutrients. This was unfed and started with only salt and 0 TDS water; it was quickly overrun with algae.

ultra-low nutrient environments far better than other organisms

What other organisms?