Help me what is this?

[EricJones9447]

I've had this for a few months now and can't seem to get rid of it. I use Ro water regular water changes ( 10% to 15%) a week I don't over feed I have one yellow tang and two ocellaris clowns.

 

[Kyle461]

Looks like diatoms (brown crud). Could get a CUC and something to sift the sand around to help with that. From what I read this is a normal outbreak and usually fixes itself. Maybe too much light as well?

 

[ryeguyy84]

what size tank?

 

[EricJones9447]

75g
lights are on for a maximum 8hr/ day
What is a Cuc?

 

[scooter31707]

CUC means Clean-up Crew. it consist of crabs, snails, shrimp, and some star fish. they clean up left over food and eat different types of algae.

 

[scooter31707]

Have you used RO water to fill up the tank. You might think you are not overfeeding, but you might be. Have you tested for phosphates? what are you readings for nirates/

 

[EricJones9447]

Right now I have 5 nassarius snails 10 turbo snails a conch and a cleaner shrimp and one blue legged hermit crab
Also I use ro water
My nitrate readings are 0
My phosphate reading are also near 0

 

[EricJones9447]

Sorry phosphates are at .35

 

[ryeguyy84]

Well there's your problem. I keep my phosphate around .04. You could get away with higher like .09 but .35 is real high.

 

[EricJones9447]

What's the best way to lower it safely?

 

[sherief.elsayed]

Water changes and possibly look into getting a phosban reactor. It would take a while but it's progress, don't expect instant results. Phosban reactors are not all to expensive as well for a 75 gallon.

 

[sticky polyps]

is it a newer tank? that's what my sand bed looked like a few weeks ago on my 4 mo old tank.. it is normal for a tank that age. even when skimming heavy, carbon dosing, running GFO and carbon in reactors and using good water,my tank went from having heavy diatoms for the first 3-4 months to having small patches of cyano and GHA. it is all part of a new tank "running in" and stabilizing. some are luckier than others, I feel bad for those who have Po4 leeching from there brand new rocks....

 

[EricJones9447]

The tank is at least 6 months old

 

[Mcgeezer]

Your phosphate is way too high. You need to manually remove the cyano by siphoning it with tubing. Then rinse the sand you removed during siphoning really well and return it to the tank.

Start running GFO to lower phosphate significantly and consider a big water change.

 

[EricJones9447]

What's the best way to add the sand back in the tank once it's rinsed off?
Also what should I do about the sand I can't get to?

 

[Mcgeezer]

I would siphon it into a mesh filter sock sitting in the sump so you don't lose any water from the system.

Then dump the sand into a small Tupperware container with some saltwater and swish it really good along with mixing the sand up to remove as much cyano and other crud as possible.

Once rinsed, dump the dirty water and do a another quick rinse/repeat.

Gently place the Tupperware holding the sand underwater in your tank and then fill back in the spots you removed by gently pouring it back in.

 

[EricJones9447]

Thanks

 

[BigCountry74]

water chnages and kill the lights for a few days

 

[EricJones9447]

I did a complete blackout for 3 days and it did kill it but it came right back after but I now have a leather coral in the tank so I'm not sure if the coral will survive a black out also my yellow tang didn't do so well during it