Pretty sure this is bleaching

[ruscar]

As you can see my zoa has steadily go down hill in the past 7 months. Pic in middle was back in June, pic on left now. I have move it to every place in the tank for weeks at a time with no change. the tank is a 55 gal (48x12x20) lights pc & t5 400 watts total. Everything else in the tank is doing well. Any suggestions? Thanks

 

[Sikryd]

I'd check your alkalinity.

What are your other levels?

 

[tranto1]

those are not zoas......

 

[dalston]

Thats a favia not zoas, you will get a better answer in the LPS forum.

That being said, it would help to post your params (with numbers)

 

[tahoe61]

Bleaching

Bleaching

As previously stated not zoas.
1. The first pic does indeed look bleached.
2. Secondy pic looks like a very nice piece.
3. Hard to tell without a better pic.
4. Need parameters.
Good luck.