corals turning white at bottom

[mikea213]

Any one got any idea what's causing this? It almost looks like something is eating it. It's been doing this over the last few months and nothing has been added or changed to the tank.

Thanks











Tank is 180g
2 mp40
2 EVO 250w LEDs
Calcium reactor
Ev-240 skimmer
Phos reactor running 2 cups of phosguard

Temp 78
Salinity 1.025
Ph 8.3
Mag 1350
Nitrite 0
Nitrate 0
Alk 2.8 mlq
Calcium 400
Phos .35ppm

The corals have been in this same spot for over a year.

 

[ccCapt]

Phosphate is high for SPS corals. The recommended level is around 0.03.
Reef Aquarium Water Parameters by Randy Holmes-Farley - Reefkeeping.com

 

[mikea213]

Whats a safe way to bring them down? I'm running phosguard per the instructions on the bottle of 1 cup per 75-100 gal. Should I add more to the reactor ?

 

[ccCapt]

I would not use Phosguard at all. It's aluminum based and is know to irritate some corals. I would switch to an iron based (GFO - granular ferric oxide) phosphate remover.

 

[mikea213]

What brand do you recommend? My local stores only sell the phosgaurd and the kent brand.