sps decoloration

[msantama]

Hello
Some know why the acropores are fading??
I was using coral system from zeovit for 2 months and I stopped using it 3 weeks ago

My tank has 800 liters of net water
kH: 7
Ca: 450
Mg: 1340
No3: 1
PO4: 0
I add only coral system 3 (Aminoacids)
I hope you can help me
Thanks in advance

two month ago
001 by mgsantama

today
002 by mgsantama

IMG_2019 by mgsantama
IMG_2017 by mgsantama
IMG_2018 by mgsantama

 

[Mr.Fishtank]

It is hard to see what is going on in the pic's. But it looks like stn to me. Could you post some pic's without the blues? Also double check your test. Where is your S.G?
Did you stop the KZ all at once. Changing things too quickly can be an issue. And if your phosphates are truly zero that will also be a problem.

 

[jda]

Nobody ever thinks that they have pests when their corals start to lose color out of nowhere. I hope that you don't have any, but check and check a few more times just to be sure.

 

[msantama]

thank you
I'm going to check that

 

[msantama]

Thank you
I found an orange snail on the acropora

IMG_2070

 

[jda]

Post that in the invert forum and see if anybody knows what it is. Also, keep looking.