Algae bloom

salty105

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I’ve been gone a week and while I was
Gone the algae went crazy. I was running the system without a filter sock to try to get nitrates up (still too low now). But that skyrocketed the phosphate.

Ammonia-0
Nitrite-0
Nitrate-.5 ish close to 0
PH-8.1
Phosphate-.5ppm
Alk-10.1

I’m doing a water change today to try to get those phosphates down, and then I’ve bought a supplement to get nitrates up.

How ever. I feel like I’ve run into a bad case of Cyanobacteria. I’ve taken some pics

What could I do to battle it?

I’m still new, and the tank is 4 months old
20260412_150457_751B480A-D3E8-40D2-8F1D-546456FD5D18.png

20260412_150457_6A396DE2-6120-46D9-BF30-F207FFC1DD49.png
 

Mr. Mojo Rising

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Personally I would just ride it out and not mess with the system. Its not uncommon to come from a week long trip and find lots of algae in the tank, often the result of using the feeder with pellets or flakes. I find it does takes a few weeks to recover.
 
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salty105

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Personally I would just ride it out and not mess with the system. Its not uncommon to come from a week long trip and find lots of algae in the tank, often the result of using the feeder with pellets or flakes. I find it does takes a few weeks to recover.
I should still do the water change right? .5 on phosphates is too high from what I’ve seen online
 

CaptainScuba

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I should still do the water change right? .5 on phosphates is too high from what I’ve seen online
To my knowledge a water change wont really decrease your phosphates. It is bound to the rock & sand in your display and as soon as you add new "clean" water (0ppm phosphate), the phosphate contained within your sand and rocks will leach out rapidly and your phosphates will be relatively the same amount. There are many ways to lower phosphates but I have NO experience with any of them. I actually have the opposite issue; I can't keep my phosphates off of 0ppm unless I'm constantly dosing them. 0.5ppm phosphate is relatively high and 0.5ppm nitrate is relatively low. I would do a little research on different ways to remove phosphates and pick one that best suits your situation.

I also don't have much experience with cyanobacteria either; but I do believe that cleaning up your phosphates should head you in the right direction.
 

fish_collector

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Siphon out as much of the algae and cyano as you can when you do your water change. 0.5 phosphate isn't a big deal depending on what's in the tank, but even then 0.5 phosphate isn't a big deal. At 5 months you won't be able to manage nutrients very well, the hard truth is you just have to deal with it until the tank is older.
 
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salty105

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Siphon out as much of the algae and cyano as you can when you do your water change. 0.5 phosphate isn't a big deal depending on what's in the tank, but even then 0.5 phosphate isn't a big deal. At 5 months you won't be able to manage nutrients very well, the hard truth is you just have to deal with it until the tank is older.
Ill definitely do that!

Im not worried about the look I just want my one clown to survive (she’s doing good so far) seeing her partner died a month ago. I have a few snails and a single emerald crab as well. I also have a gsp coral which looks to be struggling hence me wanting to dose some nitrate to make it do better. I’m also still over feeding a bit. Should I stop that?
 

Mr. Mojo Rising

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I’m also still over feeding a bit. Should I stop that?
I'm not sure what that means, but me personally I feed my fish 3-4 times a day, small amounts, I like the see the food gone in less than a minute. If I still see food flying around after a minute, I slap myself on the wrist for overfeeding. Uneaten food rots and increases the dissolved organics which I'm convinced is the main fuel for algae.
 
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salty105

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I’m also still over feeding a bit. Should I stop that?
I'm not sure what that means, but me personally I feed my fish 3-4 times a day, small amounts, I like the see the food gone in less than a minute. If I still see food flying around after a minute, I slap myself on the wrist for overfeeding. Uneaten food rots and increases the dissolved organics which I'm convinced is the main fuel for algae.
Sounds good then I’m definitely feeding too much, I’ll cut back on that to your suggested amount. Would you suggest me dosing some nitrate to get atleast something in the tank?
 

Mr. Mojo Rising

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Sounds good then I’m definitely feeding too much, I’ll cut back on that to your suggested amount. Would you suggest me dosing some nitrate to get atleast something in the tank?
lol I'm the wrong guy to ask that question, I'm very happy with my nitrates at 5. I know most folks like them higher but not me

I also never suggest to dose nitrate when there is an algae problem. Algae consumes nitrate/phosphate very quickly, so depending how bad the algae is, dosing might actually feed the algae.
 

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