Corals color not coming back - translucent

[gabe.mihu]

Hi, I have a 75g for about a year, a few corals, had an ammonia spike about 2-3 months ago, had to move corals out, tank went through a new cycle.
Corals have been back in the tank for about a month, some are coming back to folly extent and colored.

However, palythoa and a couple of zoas are half open/half closed and polyps are nowhere close to being as colored as they were before the ammonia spike, some polyps are actually translucent:

- cyphastrea, electro leptoseris, lightning tip leptastrea, psammocora are getting back their color, they seem to be doing amazing (!)
- palythoa went from dark brown/purple, 1 inch polyps (before ammonia spike) to translucent, partially closed, half inch polyps
- zoas opened up after the return, now they are not opening up as much
- goniopora slowly coming back to life
- my duncan whisker doesn't even care, he's very good, although does not extend as much yet

Question: is there anything I can do except just wait? Light is the same as before, just dimmed a bit (two REEFLED 50); coral positioning similar to as before. Water chemistry is good: phosphates 0.06, some nitrates, rest all within a good range. Feeding fish 5 times a week, corals 3 times a week - reef roids, fish eggs, dry food, mysis shrimp.

 

[Oldreeferman]

This is my take, if i was you and its only the Palys effected id rid the DT of them stat.
The reason is when/if they spread & take over any live rock they will be impossible to remove without tossing said rocks due to palytoxin dangers so you may want to read up on this poison before allowing too much growth to take hold. LF stores do not explain these dire issues, and i know personally several people that work in 2 local stores that just dread cleaning tanks with them as they always get sick with flu like symptoms afterwards and that is a minor symptom....... can get much worse so. Imagine if the water heater stuck in the on position & cooked them in the house? The toxins can then vaporise into the air and enter the lungs then. YIKES.......

 

[Timfish]

Be patient. It can literally take months for corals to recover from bleaching and recovery time will be species specific (from my experience can be colony specific). Start feeding your fish everyday and stop feeding your corals. Fish poop is the best source of nitrogen, phosphorus and carbonates for your corals. This research done by University of Hawai'i shows how difficult it is to determine which corals should be fed and how much to feed the ones that do want to be fed.

Fig. 3 from This papaer looking at nutrients on corals

 

[gabe.mihu]

Thank you both for your input, this is great info and advice!!

I watched the palys closely since I have seen these posts, they are getting better. I was thinking about isolating them, but they seem to be improving - I will keep a close eye on them. Regarding the rest of the corals, 90% are back on track, it's very interesting how they regained color. I kept on studying APR on the 50W and I believe I am running the tank on very low APR at this moment (which might have helped with getting the corals back on track). I also will most probably redo the aquascape, as in the last 3-4 weeks I have been studying a lot regarding coral types, growth, parameters, and I have a better idea of how everything fits within the aquascape.

Thank you, both. Again, I did pay a lot of attention to your advices.

Gabe