New Favites in trouble?

[Moonwrassler]

Hi, folks.
My son and I are adding corals to what had been a FLOWLR tank. We recently picked up 6 new frags, that have been settling in in a QT for the past week. At first everyone seemed happy. But then yesterday (6days after arrival) we noticed our new Pyrokinesis Favites starting to develop a grayish spot on the top of him. It's really pronounced under the blue/moon light at nighttime. Day and night pics below.
1. Does this look like a sick coral to you? (Pls forgive the noob question, we don't want to overreact, but this looks bad to me.)
2. What's likely cause? Possible fix?
a. My first thought was " too much light?" When we first got the shipment we put the frag rack on a rock about 7" down from surface under the LED strip that came with our first Fluval AIO 32gal tank (which is now our QT). Started to see some color fade and polyp retraction, so we moved it down to bottom of tank after 2 days. This splotch showed up 3 days later.
b. Other possibilities require a bunch more data, I know. We've tested lots of stuff with Red Sea kits, and parameters all look like what were told is "good." (I'll list below if anyone wants to read through). The only other livestock in the tank are some snails. Tank is over a year old, no algae issues, only significant change is that once we put in corals what had been a 9.4dkh tank drifted down over a week to 8.1dkh. We added Red Sea Foundation to get it back to 9.0 last night, and will add a little more to get to 9.5 tonight. Are Favites super-sensitive to Alk variance? It's just odd that everyone else in tank seems fine...
Thanks for any insights.

32 gal AIO tank, 1.5years old
salinity 1.024
Temp 77
ammonia, nitrite both 0
Nitrate 10 (tank used to have three fish and a shrimp)
Alk 8.1, down from 9.4 last week
pH 8.0 (down from 8.4 last week)
CA 430
Mg 1360

 

[Wasabiroot]

Get alk stable, could be mad about that. Everything else looks fine. What are your phosphates at?
Any fish with potential to take a nip? Angels, bicolor blenny, etc?

 

[Moonwrassler]

Come to think of it, the dwarf flameback angel was pecking at him. Funny, he never bothered anyone else.
Also had a skunk cleaner shrimp that would crawl around--but that was equal opportunity.
Why would angel focus on just one coral?

 

[Wasabiroot]

Dwarf angels are reef safe with caution and it depends on the individual. That being said, anecdotally when I had fish preying on coral, they love the fleshy easy stuff. Favia, leptoseris, cynarina...anything that's easy to take a quick nip from without a nasty sting maybe?
You could try target feeding the angel to discourage it from tasting things. But he may already have added coral to the menu...would be monitoring him/her

 

[vetteguy53081]

Your levels look good, however, concerning are nitrates at zero.
What test kits are you using ?
Moderate light and water flow for these guys. What is age of tank ?
Take salinity to 1.025

 

[Wasabiroot]

Your levels look good, however, concerning are nitrates at zero.
What test kits are you using ?
Moderate light and water flow for these guys. What is age of tank ?

That's nitrites at 0 it appears

 

[Wasabiroot]

I agree with vetteguy tho, now that the tank is not fowlr I'd raise it to 35ppt. That's my personal preference anyhow

 

[Moonwrassler]

Thanks to all for the guidance. Will follow on all points.
Interesting point about leptoseris. We have one of those too, who was starting to look a little brown in places, and I fear it may have been that Angel. Might need to just keep him away for a few weeks and see how it goes.

 

[MaxTremors]

A couple things. First, all stony corals are sensitive to Alk swings. You don’t want to raise your Alk a whole point in one day, you’d want to do it over a week or so, don’t raise it anymore today, try to just keep it stable where it’s at (IMO, 9dkh is preferable to 9.5 anyway). I would test your Alk every day at the same time each day (log the results) to get an idea of how much Alk your tank is consuming, you can then figure out if you need to dose and if so how much, again ideally you want it to be stable (for example in my tank, I shoot for 8.5 dkh, and add the equivalent of 0.4dkh to maintain it), after that, you’ll want to test a couple times a week just to verify that your consumption hasn’t changed.

I would recommend getting a phosphate test kit. Make sure that it has a resolution that is specific enough for reefing, ideally it would go as low as 0.01, 0.02, 0.03, etc. The Hanna ULR Phosphate checker is the best IMO, but Tropic Marin has a really good kit that is only $20, and Red Sea’s is also decent.

I would also get your salinity up to 1.025/26 or 35ppt. Are you using a refractometer or hydrometer? Also, are you using RODI water?

Do you have an Angel fish in the same tank? If so, that could be the issue. Otherwise, just work on ensuring stable parameters, stability is more important than being slightly out of the suggested range. Avoid any spikes or dips in either direction, if something is off, you want to slowly correct it, not all at once.

 

[Moonwrassler]

Thank you.
Unfortunately all I have right now is the junky API PO4 test, which claims I have 0.25 phosphate. We will invest in a good test so we can have real numbers.
Also, I fear I mixed up the Ca and Mg readings from the new tank with the old one. The corals are in the old tank which is at 1240 Mg, 380 Ca, and 9.0 dKH with an 8.2 pH.
Rather than messing with dosing I think I'll just do a 20% water change (yes, I'm using RO/DI water with 0 tds) with Reef Crystals at 1.026 (spectrometer measured) and then wait a day to see where the levels land.
Was gone till late this evening, and most of the coral frags were more closed up than in the past. Maybe the water hasn't been as stable as I'd thought.
Will do the water change and follow up with any developments.

 

[Moonwrassler]

Happy to report that the coral seem to be improving. Unfortunately we have a new sad tale of the sudden death of a beautiful new melanarus wrasse.
Wandered into my nice LFS on Thursday and saw him, 2.5 inches, gorgeous, and couldn't resist.
Brought him home, acclimated for 40 mins, released, and he dove right into the sand bed.
Friday morning he shows up and eats with everyone else (flameback dwarf angel, neon indigo dottyback, and black ocy clown). Don't see him Friday night but assumed he "went to bed."
Found him dead on the sand bed this morning.everyone else is happy. Water parameters stable.
Is this an Ammonia Bomb problem? We haven't really dug up the sand in the last couple water changes, but it was stirred up pretty good about a month ago. Would anaerobic bacteria take over that quickly?

 

[DeniseAndy]

I may have missed some of this, but most of the others seem to have touched on getting the alk settled and the angel may be picking. One other thing aobut that particular "favia" is it is pretty hardy. I would get it in lower light and lower flow. Needs some nitrates as others mentioned.
Put a mesh around it if needed to keep angel off. Should be able to come back. I have had similar go to one ppolyps and now are 5" across.