Could raising Magnesium or changing GFO cause algae bloom?

[snaza]

Hi,

Sorry for the weird question but i'm getting a bit of brown looking diatoms on the substrate, as well as what looks like a bit of algae die off and air bubbles on the live rock. I've always had a bit of light fuzz on the live rock and now it looks like it is dying.

After testing water parameters a week ago i found P04 0.05 on hanna and Mag 1180. I dosed mag and change GFO to get them back to 0.02 and 1280. Since them i've had the algae outbreak.

Any ideas?

All other params are in check.

cheers

Aaron

[ridetheducati]

Check your source water.

[snaza]

Check your source water.

Rodi tds is 000. Using nsw

[bertoni]

If the brown on the sand is diatoms, many snails should eat it.

Is the algae currently growing larger or dying back? I'm confused on that.