diatoms?

[DS5000]

Tank is about 2.5 months old, mixed reef 45gal. I had diatoms about 2wks ago, that resolved with some phosguard, I thought without issue. I had about a week of pristine sand, then brown appearing growth appeared back on sand. I figure I dropped my phos too low with the phosguard, after the first treatment?
My parameters

alk 8.5
pH 8.2
N03 2-10
phos 0.0 - not using ULR hanna, just the 'regular one'
using RODI water
carib liferock
sandbed
have 3 trochus, 3 nasarrius, 1 emerald crab, 4 fish

The growth has the same appearance as before.

I need to measure my phos better, so may Ill get the ULR hanna.
Ill up my feeds and get my phos up, and maybe that should help?

thx

 

[glb]

Your tank is pretty new so diatoms are common. If your PO4 zeroed out you might have dinos. I’d raise the PO4 with extra feeding until you get a reading and see if that helps. Be patient! New tanks go through an ugly stage no matter what, so hang in there!

 

[Miguel Negron]

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