Cloudy tank, bacterial bloom?

[becerril17]

Hi all,

3 days ago one of my tanks became cloudy. I’ve read it could be a bacterial bloom but I wanted to get some opinions on here. This tank is a 40g breeder that runs off of a canister filter. There are two large clownfish, 8 BTA’s some Zoas a Galaxia and a fox coral currently in the tank. All of the coral and the fish seem to be doing great but the nems do seem smaller than usual. I might have over fed a bit and thought that was why the tank was cloudy. I did a large water change but it did not help at all. Someone suggested getting a small UV sterilizer but then I heard that by doing that it could make it worse. Advise ?

Current parameters as of today 7/13/23

Temperature 79 degrees F
Salinity 1.024
pH 8.0
Alkalinity 8.7
Calcium 420-430
Nitrate 5.0
Phosphate 0.10
Ammonia 0

 

[chaples55]

Could you post pictures? What color is the cloudiness? Greenish? Brownish? Whitish? That will help determine what the cause is.

Since you're using a canister filter I assume you don't have a protein skimmer? That would be my first line of defense for any kind of bloom because it will actually remove it from the water and not just sterilize it. I recently had a phyto bloom in a quarantine tank (greenish brown water). Could hardly see a foot into the tank. Installed a small skimmer and it filled the cup 3 times over the course of a couple hours and got the tank clear again.

Another possibility is snails or some other critter spawning. That would make the water milky white. Without a skimmer that could linger in the water as well.

A bacterial bloom would also be whitish, but less milky. Could be caused by overfeeding like you said.

Whatever the cause, you'll want to make sure the tank is heavily aerated because some kinds of blooms can deplete oxygen in the water. If you don't have a skimmer a small HOB unit would be your best bet I'd say.

 

[becerril17]

I will take pictures as soon as I get home. It started out a milky white but now it’s less milky and just a hazy look to it. Not green though, just white

 

[becerril17]

@chaples55 the photo isn’t showing how cloudy it really is. Tomorrow I’ll send you a photo in the white light. It looks like it’s starting to clear up some but compared to my other tank this one looks super hazy.

 

[gill]

I hope this cleared up. It just happens sometimes. I would add flow/bubbles of some sort, to keep oxygen up, that is the real hazard while it works itself out because oxygen levels will drop.

 

[lmm1967]

a bacterial bloom will typically also show slime someplace as well - might only be a slightly slimy film on inside of glass - all the way up to strings flowing in the water column. Neither is harmful as long as you keep flow really high for O2 levels and are comfortable that its getting better and not worse.

 

[ecoreefguy]

It must be something in the water. Serveral people have recently, including YouTubers , had really bad blooms killing some, if not all fishstock.