Dino, diatoms or cyano?

[a123h]

Tanks been running 5-6 months nitrates 2 phosphates 0 none present. Water changes every 2-3 weeks (will start being more strict). Ive had this going on for a while so just want to know is it a nutrients low issue and how to fix. Lights on for 8 and half hours a day. Im thinking dino it does have bubbles on some areas as you see. Been feeding more and start reefroids to up nutrients. Also its hard to vaccum up its literally stuck to the sand.

 

[fishface NJ]

White light please

 

[a123h]

White light please

Should have put it from the start

 

[EnterName]

Diatoms attach themselves to sand grains from time to time which could be the issue. But both dinoflagellates and diatoms may be present. A microscope would help.

The tank is 5-6 months old so you should be past the diatom phase by now. Is it possible that your water changes introduced more silicates? Sooner or later the ion exchange resin of RO/DI systems is depleted and needs to be replaced. A TDS meter or pure water tester that measures conductivity can help to detect if the used RO/DI is actually clean enough. Even if you buy RO/DI this can help to detect insufficiently purified water.

I wouldn't try to increase phosphates with reef roids. You are just increasing organics that might cause issues later. Instead you can dose phosphate directly: https://www.reef2reef.com/threads/diy-phosphate-dosing-recipe.1109919/

There is a constantly ongoing equilibrium reaction between phosphate and calcium carbonate (rocks and substrate) in your tank, which binds and dissolves phosphates. If the calcium carbonate is not yet saturated enough this equilibrium reaction prevents phosphate from reaching detectable levels. Dosing phosphate will help to saturate the rocks sufficiently to keep dissolved phosphate levels above 0.01ppm. I can highly recommend getting the ULR Phosphate checker from Hanna Instruments to be able to detect low levels.

 

[a123h]

Diatoms attach themselves to sand grains from time to time which could be the issue. But both dinoflagellates and diatoms may be present. A microscope would help.

The tank is 5-6 months old so you should be past the diatom phase by now. Is it possible that your water changes introduced more silicates? Sooner or later the ion exchange resin of RO/DI systems is depleted and needs to be replaced. A TDS meter or pure water tester that measures conductivity can help to detect if the used RO/DI is actually clean enough. Even if you buy RO/DI this can help to detect insufficiently purified water.

I wouldn't try to increase phosphates with reef roids. You are just increasing organics that might cause issues later. Instead you can dose phosphate directly: https://www.reef2reef.com/threads/diy-phosphate-dosing-recipe.1109919/

There is a constantly ongoing equilibrium reaction between phosphate and calcium carbonate (rocks and substrate) in your tank, which binds and dissolves phosphates. If the calcium carbonate is not yet saturated enough this equilibrium reaction prevents phosphate from reaching detectable levels. Dosing phosphate will help to saturate the rocks sufficiently to keep dissolved phosphate levels above 0.01ppm. I can highly recommend getting the ULR Phosphate checker from Hanna Instruments to be able to detect low levels.

I was thinking it could be my water ill get a TDS checker. I was also planning to dose phosphates, i was going to give it 2 weeks with feeding more and reef roids twice a week to see if nitrates and phosphates may increase but may as well dose phosphate as you said ill check out that link. My corals are not happy too. Reason for reef roids was i got lps coral they pretty much nearly died first few hours in and soft coral is closed so been trying to up nutrients and bring up Alkalinity.

 

[EnterName]

Diatoms attach themselves to sand grains from time to time which could be the issue. But both dinoflagellates and diatoms may be present. A microscope would help.

The tank is 5-6 months old so you should be past the diatom phase by now. Is it possible that your water changes introduced more silicates? Sooner or later the ion exchange resin of RO/DI systems is depleted and needs to be replaced. A TDS meter or pure water tester that measures conductivity can help to detect if the used RO/DI is actually clean enough. Even if you buy RO/DI this can help to detect insufficiently purified water.

I wouldn't try to increase phosphates with reef roids. You are just increasing organics that might cause issues later. Instead you can dose phosphate directly: https://www.reef2reef.com/threads/diy-phosphate-dosing-recipe.1109919/

There is a constantly ongoing equilibrium reaction between phosphate and calcium carbonate (rocks and substrate) in your tank, which binds and dissolves phosphates. If the calcium carbonate is not yet saturated enough this equilibrium reaction prevents phosphate from reaching detectable levels. Dosing phosphate will help to saturate the rocks sufficiently to keep dissolved phosphate levels above 0.01ppm. I can highly recommend getting the ULR Phosphate checker from Hanna Instruments to be able to detect low levels.

I was thinking it could be my water ill get a TDS checker. I was also planning to dose phosphates, i was going to give it 2 weeks with feeding more and reef roids twice a week to see if nitrates and phosphates may increase but may as well dose phosphate as you said ill check out that link. My corals are not happy too. Reason for reef roids was i got lps coral they pretty much nearly died first few hours in and soft coral is closed so been trying to up nutrients and bring up Alkalinity.

Ammonia is the preferred nitrogen source, so I can recommend dosing ammonia if you feel the need to increase nitrate as well:

Thread 'DIY Ammonia dosing for low nitrate systems'

May 23, 2023

Some reef aquaria have chronic low nitrogen availability. One indicator is very low nitrate. Nitrate dosing is a fine remedy, but it is possible that ammonia dosing may be more beneficial for some organisms since ammonia can be energetically easier to assimilate than is nitrate.

For this reason, I thought it would be useful to provide some DIY directions for ammonia dosing.

There are many materials that could be used for ammonia dosing, including some household ammonia solutions, but in order to give better assurance of purity, I'm electing the show directions using food grade ammonium...

• Randy Holmes-Farley
• Replies: 1,743
• Forum: Reef Chemistry by Randy Holmes-Farley

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• 
• 

If you need help with any of those recipes let me know. I'm dosing both myself daily.

 

[a123h]

Nitrate is low but not completely bottomed out im more so looking to get phosphates up as its 0 judging by the salifert test kit. I will also look into the hanna phosphate checker. So do you recommend just dosing phosphates then and checking my tds etc?

 

[allof fish]

I was thinking it could be my water ill get a TDS checker. I was also planning to dose phosphates, i was going to give it 2 weeks with feeding more and reef roids twice a week to see if nitrates and phosphates may increase but may as well dose phosphate as you said ill check out that link. My corals are not happy too. Reason for reef roids was i got lps coral they pretty much nearly died first few hours in and soft coral is closed so been trying to up nutrients and bring up Alkalinity.

Are you using rodi water? Definitely check your tds. I would go against using reef roids as your phosphates will spike but it doesn’t do much for nitrates. If you’re feeding frozen add a little more of the water which contains a lot of phosphates. When you run into issues like this you nutrients can be to blame as they are pretty low. Shoot for 5 nitrates and .05 phosphates

 

[a123h]

I was thinking it could be my water ill get a TDS checker. I was also planning to dose phosphates, i was going to give it 2 weeks with feeding more and reef roids twice a week to see if nitrates and phosphates may increase but may as well dose phosphate as you said ill check out that link. My corals are not happy too. Reason for reef roids was i got lps coral they pretty much nearly died first few hours in and soft coral is closed so been trying to up nutrients and bring up Alkalinity.

Are you using rodi water? Definitely check your tds. I would go against using reef roids as your phosphates will spike but it doesn’t do much for nitrates. If you’re feeding frozen add a little more of the water which contains a lot of phosphates. When you run into issues like this you nutrients can be to blame as they are pretty low. Shoot for 5 nitrates and .05 phosphates

Yeah im using ro di but the filters could be time to change. I do use the water for forzen and feed twice a day but its not increasing nitrates or phosphates.

 

[allof fish]

Yeah im using ro di but the filters could be time to change. I do use the water for forzen and feed twice a day but its not increasing nitrates or phosphates.

Do you have any other algae in the tank. Remember that the nitrate and phosphate numbers are what is left over from being used. Algae tends to use nutrients much faster than corals so you may have phosphate at times bit when you test its 0 because it’s being used up fast

 

[a123h]

Yeah im using ro di but the filters could be time to change. I do use the water for forzen and feed twice a day but its not increasing nitrates or phosphates.

Do you have any other algae in the tank. Remember that the nitrate and phosphate numbers are what is left over from being used. Algae tends to use nutrients much faster than corals so you may have phosphate at times bit when you test its 0 because it’s being used up fast

Mostly just what i show in pics and little hairs i dont know how to explain i have a photo grown all over my rocks and back glass i dont think its algae but its there if you see in someof my pics and zoom in you can tell.

 

[gorilla]

hard to tell kind on in between. if it dispears at night comes back during the day its dino. its there all the time its cyano

 

[a123h]

hard to tell kind on in between. if it dispears at night comes back during the day its dino. its there all the time its cyano

I think its always there

 

[EnterName]

Nitrate is low but not completely bottomed out im more so looking to get phosphates up as its 0 judging by the salifert test kit. I will also look into the hanna phosphate checker. So do you recommend just dosing phosphates then and checking my tds etc?

You can also mix a phosphate solution but in my opinion dosing phosphate requires a really good phosphate test or you risk overdosing accidentally. The previously mentioned Hanna Checker will do the job:

Thread 'DIY Phosphate Dosing Recipe'

May 3, 2025

Sometimes phosphate can be so stubbornly low that the only way to meaningfully raise it is by directly dosing phosphate.

When you feed foods, you’re adding nitrogen, carbon, and loads of organics. This effect is compounded if you’re trying to offset rocks that initially work against you by binding up most of the PO₄ until a higher equilibrium is met. It’s much cleaner and more cost-effective to purchase pure sodium phosphate online than to use hobby-grade products with unknown purities and byproducts.


You can mix sodium phosphate with nitrate, ammonium, or even add it to an ATO...

• Miami Reef
• Replies: 78
• Forum: Reef Chemistry by Randy Holmes-Farley

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• 
• 

Dosing nutrients during any sort of algae growth isn't necessarily the best idea though. It's possible there is more than enough already, but it's just assimilated very fast (same for ammonia and nitrate).

 

[a123h]

Nitrate is low but not completely bottomed out im more so looking to get phosphates up as its 0 judging by the salifert test kit. I will also look into the hanna phosphate checker. So do you recommend just dosing phosphates then and checking my tds etc?

You can also mix a phosphate solution but in my opinion dosing phosphate requires a really good phosphate test or you risk overdosing accidentally. The previously mentioned Hanna Checker will do the job:

Thread 'DIY Phosphate Dosing Recipe'

May 3, 2025

Sometimes phosphate can be so stubbornly low that the only way to meaningfully raise it is by directly dosing phosphate.

When you feed foods, you’re adding nitrogen, carbon, and loads of organics. This effect is compounded if you’re trying to offset rocks that initially work against you by binding up most of the PO₄ until a higher equilibrium is met. It’s much cleaner and more cost-effective to purchase pure sodium phosphate online than to use hobby-grade products with unknown purities and byproducts.


You can mix sodium phosphate with nitrate, ammonium, or even add it to an ATO...

• Miami Reef
• Replies: 78
• Forum: Reef Chemistry by Randy Holmes-Farley

• 
• 
• 

Dosing nutrients during any sort of algae growth isn't necessarily the best idea though. It's possible there is more than enough already, but it's just assimilated very fast (same for ammonia and nitrate).

I thought the reason for the dinos or what ever algae going on is bottomed out nutrients so getting them up to a healthy level should help right. Ill be careful with the dosing for phosphates id it comes to that and get a hanna tester. What ever it is is like clumped into the sand its not even able to be vaccumed up.

 

[EnterName]

Nitrate is low but not completely bottomed out im more so looking to get phosphates up as its 0 judging by the salifert test kit. I will also look into the hanna phosphate checker. So do you recommend just dosing phosphates then and checking my tds etc?

You can also mix a phosphate solution but in my opinion dosing phosphate requires a really good phosphate test or you risk overdosing accidentally. The previously mentioned Hanna Checker will do the job:

Thread 'DIY Phosphate Dosing Recipe'

May 3, 2025

Sometimes phosphate can be so stubbornly low that the only way to meaningfully raise it is by directly dosing phosphate.

When you feed foods, you’re adding nitrogen, carbon, and loads of organics. This effect is compounded if you’re trying to offset rocks that initially work against you by binding up most of the PO₄ until a higher equilibrium is met. It’s much cleaner and more cost-effective to purchase pure sodium phosphate online than to use hobby-grade products with unknown purities and byproducts.


You can mix sodium phosphate with nitrate, ammonium, or even add it to an ATO...

• Miami Reef
• Replies: 78
• Forum: Reef Chemistry by Randy Holmes-Farley

• 
• 
• 

Dosing nutrients during any sort of algae growth isn't necessarily the best idea though. It's possible there is more than enough already, but it's just assimilated very fast (same for ammonia and nitrate).

I thought the reason for the dinos or what ever algae going on is bottomed out nutrients so getting them up to a healthy level should help right. Ill be careful with the dosing for phosphates id it comes to that and get a hanna tester. What ever it is is like clumped into the sand its not even able to be vaccumed up.

Sometimes dosing nutrients appears to be helping against dinoflagellates. It's counter-intuitive, but I consistently was able to get and remove microscope-verified dinoflagellates with dosing nutrients in my current system. They never grew out of hand though, which might be the indicator for when there is too much or to little phosphate available. Mine didn't care much for nitrate.

 

[allof fish]

I thought the reason for the dinos or what ever algae going on is bottomed out nutrients so getting them up to a healthy level should help right. Ill be careful with the dosing for phosphates id it comes to that and get a hanna tester. What ever it is is like clumped into the sand its not even able to be vaccumed up.

Dinos yes algae no. How long do you run your lights? I would only run them like 5-6 hrs a day if you have coral. You can go no lights if you don’t. That will help algae. I would shoot for 5 nitrate .05 phos. That will help combat both issues

 

[a123h]

I thought the reason for the dinos or what ever algae going on is bottomed out nutrients so getting them up to a healthy level should help right. Ill be careful with the dosing for phosphates id it comes to that and get a hanna tester. What ever it is is like clumped into the sand its not even able to be vaccumed up.

Dinos yes algae no. How long do you run your lights? I would only run them like 5-6 hrs a day if you have coral. You can go no lights if you don’t. That will help algae. I would shoot for 5 nitrate .05 phos. That will help combat both issues

Lights in 8 and half hours not too strong i have some lps and soft that are recovering and not doing well as seen in my other post so dont want to change up lighting.

 

[allof fish]

Lights in 8 and half hours not too strong i have some lps and soft that are recovering and not doing well as seen in my other post so dont want to change up lighting.

What is specifically wrong with coral. Changes the lights from 8-6 hrs won’t hurt them just keep intensity the same. Also what are you using to test if you didn’t say already. I wouldn’t trust anything else besides Hanna for nutrients. I would just shoot for 5 and .05, water changes to suck it out and add bacteria. Sometimes you just have to let it take its course and get through jt

 

[a123h]

Lights in 8 and half hours not too strong i have some lps and soft that are recovering and not doing well as seen in my other post so dont want to change up lighting.

What is specifically wrong with coral. Changes the lights from 8-6 hrs won’t hurt them just keep intensity the same. Also what are you using to test if you didn’t say already. I wouldn’t trust anything else besides Hanna for nutrients. I would just shoot for 5 and .05, water changes to suck it out and add bacteria. Sometimes you just have to let it take its course and get through jt

Pretty much got 2 small lps frgas candy cane and acan acclimated and drip and hours later showing skelton in very bad contiton still after almsot a week my alk was 6.8 so low and raised it to now 8. leather coral has also been closed and not opening. Guessing it was an alk an nutrients issue. All my testing is done by salifet test kits atm. I will look into getting hanna for phosphate and maybe nitrate too would the other be fine on salifert or should i get mostly hanna?