Daily Diatoms

[supertank]

Hi All,
I've got another question for the pros. I have a problem with what I think are diatoms in my tank, but like the title says, they come and go on a daily basis.
What I mean is that when the lights come on in the morning, my sand looks great. However, after about two hours, I have rusty brown diatoms show up. This cycle happens everyday, and has been for about a month now.
My tank is 75 gallons and has been up and running for a little over six months now. All my water params are good, including Phosphate readings of 0 most of the time. When my tank was really new, I had diatoms but they stayed 24/7 until they finally decided to go.
My clean up crew consists of the following:
-Sally Lightfoot Crab
-2 Emerald Crabs
-Coral Banded Shrimp
-Skunk Cleaner Shrimp
-4 Pep Shrimp
-15+ Hermits
-4 Mexican Turbo Snalis
-2 Sand Sifting Stars
Below are some pictures to show what I am talking about. The first photo was this morning 15 minutes after lights on, and the second is about three hours later.
Any advice on what to do in order to elliminate this would be greatly appreciated. Thank You.

 

[meowzer]

What kind of flow do you have? Water parameters? Type of lighting?
You can get some nassarius snails, cerith snails, a florida conch

 

[nycbob]

if its mainly on the sand, u can get a sandsifting goby to stir up the substrate. r u running any kind of skimmer?

 

[supertank]

It is only appearing on the sand, and mostly towards the front of the tank. Behind my rocks is pretty clean. As for flow, I have two powerheads (not sure of brand), and a hang on filter that is empty. Only use it for more flow, however, it will be going away soon when I finish my sump. I am also running a Prisim Skimmer Hang-On as well, but again, will be going away with the new sump. My lights are T5 HO 4x65 watts. plus moon lights. I do a 10g water change weekly.
Water params are as follows:
Nitrite, Nitrate, Amonia, and Phodphate--0
PH--8.3
SG--1.025
Calcium--470 (give or take a bit)
KH--9ish
Temp--80-82 (depending on time of day)
Nas. and Cer. snails are both on my To-Get list very soon.
Thank you for the replies, and look forward to any other advice.

 

[nycbob]

r u using rodi water? r u sure u hv t5 light bc t5 bulbs dont come in 65w.

 

[supertank]

My fault on the lights. I just looked at them, and they are 4x54 watts. 2 Acs. and 2 12000k whites. I just replaced all four of these bulbs recently. One bulb every 4 or 5 days. Sorry for the bad info. I don't know why I thought they were 65 watts.
And Yes, I only use RO/DI water for top-offs. I buy the water from my LFS for now until I get my own unit.

 

[nycbob]

if ur tank is only 5-6 months old, it could be part of the progress of a new tank. the best remedy for diatom on the sandbed is something that will stir it consistently like a conch or goby.

 

[cranberry]

Your CUC could use some pumping up in the snail department. CUCs don't fix a problem, but you are indeed lacking.
My only concern would be the massive amount of hermits you have in there that could have snails on the menu.

 

[supertank]

Snails are deffinetly on my list of things to get real soon, but as you said, I am worried about the hermits launching an offensive on them to claim there shells. I keep getting hermits as hitchhikers lately. I suppose that's a good thing though. I have got at least 7 hermits in the last couple months as hitchhikers.
Anyway, thank you for the advice.