Brown Algae on Sand -- Killin' Me -- OUCH

[aquafreak]

Hi All

I've got a brown algae problem after being away from my aquarium on business for 2 months.

Within hours, a thin hairy layer of brown algae grows quite rapidly on my aragonite sand.

I have tried good waterflow, charcoal, and phospate sponges in the filter along with rigorous protein skimming with no improvement. The water temperature is maintained at 79 degrees via an Aqua Logic chiller.

Parameters: 110 gallon glass (tall) // 30 gallon sump // CPR overflow and pump at 1100+ gph // 2 powerheads at 100 gph // RO/DI water added daily // lighting: 500 watts of MH, 300 watts of VHO in various spectrums for corals/rock

I am going to add an ozonizer to the skimmer intake in a few weeks.

I would say that I need a bigger cleanup crew and am adding snails and hermits and emeralds weekly.

What am I missing that is so hard to keep this under control? Does anyone have any more advice to give to a pretty hardworking learning reef keeper....I've given advice on this myself before and now I'm stuck....Please help!

[MT79]

Brown diatoms- usually caused by excessive silicates or [acronym:4872563b93="Phosphate"]PO4[/acronym:4872563b93]'s. Feed "cautiously", keep up w/ weekly [acronym:4872563b93="Partial water change"]PWC[/acronym:4872563b93]'s, and use [acronym:4872563b93="Granular Activated Carbon"]GAC[/acronym:4872563b93]. Have you checked your [acronym:4872563b93="Reverse osmosis"]RO[/acronym:4872563b93]/[acronym:4872563b93="Deionization"]DI[/acronym:4872563b93] unit lately? It may be time for a [acronym:4872563b93="Reverse osmosis"]RO[/acronym:4872563b93] and/or [acronym:4872563b93="Deionization"]DI[/acronym:4872563b93] replacement. [acronym:4872563b93="Hope this helps (or) Happy to help"]HTH[/acronym:4872563b93]

[i have crabs]

phosphate/silicate remover if your on tap water could help

[aquafreak]

Okay, thank you. What is GAC? Is a PWC a pure water change?

[seaham358]

[acronym:3ead95df4a="Granular Activated Carbon"]GAC[/acronym:3ead95df4a] is carbon...
[acronym:3ead95df4a="Partial water change"]PWC[/acronym:3ead95df4a] partial water change...
Test you water for nitrates, phosphates and silacates and post the readings. It is feeding off excess nutrients from some where. Check your top off water also.
Who was watching the tank while you were gone?
Maybe they were over feeding the little begger fish.?
Were any water changes done while you were gone?
Do like the others say, water changes and test water..