Need Advice

[hadams356]

Parameters all test done with Hanna's checkers

Alk 9.3
Ca 467
Mg 1363
PO4 .11
NO3 1.5

Been battling what I think are diatoms for several months now. Did the h202 test to determine which algea I am fighting. Test came back to what appeared as dust in bottom of container no corgaulating of sediment. Algea doesn't have any bubbles like dino nor matting like cyano.

What I have done so for
1 checked rodi water zero tds, changed filters anyway
2 tested for silicates in both makeup water and tank both test came back zero for silicates
3 On day 2 of my second 3 day blackout in 5 weeks. Just peeked in on tank and still have brown patches on sand bed.
4 vacumn sand and blown rocks off numerous, numerous times
5 I do 30 gallon water changes weekly on 200 gallon system
6 Used Chemiclean once about 4 weeks ago to no effect what so ever.
7 Been dosing 20ml Microbacter7 daily for about 10 days

About at wits end any suggestions appreciated

Pic 1 tank, pic 2 under cheap mircoscope

 

[randomfishdude]

Did you try more flow? Along with more cuc?
I had simalar issue and I put some more flow on the sandbed, got 2 conch(can't spell) and a goby.

 

[hadams356]

Yes, I tried more flow, 200 dollars worth of snails, pods and crabs