Corals aren't opening and I'm getting frustrated.

[matt20]

Hello, I'm not sure if this is the correct sub-forum to post this in since I'm not used to posting on RC. I posted a thread on another forum about a problem I've been having for the past two or so weeks. I've gotten quite a bit of help but no one has been able to give a definitive answer, so I thought I'd try asking here. Sorry for the wall of text but I'm just trying to be thorough.

I've had a 20 gallon reef set up for about 2 months now. I started with dry sand and rock, and cycled using Dr. Tim's bacteria and ammonium chloride. The cycle took a little over two weeks. After the cycle finished I added my pair of clownfish from a previous build, and waited another week to make sure their addition didn't cause any ammonia/nitrite spikes. After that I added a clean up crew and some tester corals I had sitting in quarantine. Everything was open within hours and looked great for about two weeks. Then about two weeks ago, everything started closing up. I tested my parameters several times and had them verified by my LFS - nothing was out of the ordinary. I figured I'd just wait it out, but here I am two weeks later and everything is still closed up with the exception of a small toadstool leather that doesn't seem to be affected. The fish and invertebrates remain unaffected. What could cause corals to be happy for two weeks, then become stressed all of a sudden?

Here are my parameters:

SG: 1.025 (calibrated refractometer)
Temp: 78F +/-0.1
pH: 8.1
NH3: 0ppm
NO2: 0ppm
NO3: <0.2ppm
PO4: 0ppm
Ca2+: 460ppm
Mg2+: 1400ppm
Alk: 8.0dKH


Equipment:

20 gallon long glass tank
AC70 filter. I was running a low dose of carbon and gfo but took that out about a week ago in case my water was too clean. No real change since then. Right now there's just a ball of chaeto in there.
4 bulb HO-T5 fixture
Vortech MP10
Cobalt Aquatics 100W Neo-Therm heater
Tunze Osmolator ATO
No sump, no skimmer


What other people have suggested:

Stray voltage? Nope, checked for it.
Light shock? Possible. The corals were under a Par30 bulb in quarantine before going under the T5s. I've never had this serious of an issue with improper light acclimation though, so I am less inclined to believe this.
Contaminated salt/water? I don't think so. I use distilled water and Reef Crystals salt. If any of those were contaminated with some toxin, copper, or heavy metal then I don't think it would have taken two weeks for things to show signs of stress. Also the invertebrates, fish, and a single toadstool leather frag aren't affected by whatever is going on. I also used the same salt and water in the fish/coral quarantine tank with no ill effects.
Water is too clean? This is the best suggestion I've had so far, but I'm still not 100% sure. I did start with completely dry rock and sand, and was using small doses of carbon and GFO for a while. I have since removed those things in case the water is too clean, but I haven't seen any change in the week since I've done that.



Thanks in advance for your suggestions. It's really frustrating to have everything looking so stressed with no obvious reason for it. I'm hoping I can fix whatever's going on with some more help.

[marvelousone]

what type corals are we talking about.

[matt20]

what type corals are we talking about.

A small mix of LPS and softies. I have a frogspawn frag, ricordea mushroom, a couple zoanthid frags, a tiny leather frag, a green candy cane frag, and a torch coral frag.

[marvelousone]

If your water is to clean it might take more than a week to improve. As far as lighting i don't think thats it. You can move them to the bottom. Make sure you have good flow on them. I have most of those and seem happier in high flow. Normally my green toadstool is my indicator something is wrong.

[ACBlinky]

Have you done any water changes and/or run carbon since the tank was set up? I'm wondering if allelopathy is playing a role here; leathers are notorious for releasing noxious chemicals into the surrounding water and euphyllia corals (torch, hammer, frogspawn, bubble) can send out nematocysts that are invisible to the eye that will sting nearby corals. Corals are in a constant state of war, and it can be very difficult to keep a varied mix of softies and LPS in a small tank. Carbon and water changes may help if your corals are fighting -- if you do a 25% wc, run carbon and everything opens back up you might want to consider using carbon regularly (or 24/7) to keep the toxins at bay.

[matt20]

Have you done any water changes and/or run carbon since the tank was set up? I'm wondering if allelopathy is playing a role here; leathers are notorious for releasing noxious chemicals into the surrounding water and euphyllia corals (torch, hammer, frogspawn, bubble) can send out nematocysts that are invisible to the eye that will sting nearby corals. Corals are in a constant state of war, and it can be very difficult to keep a varied mix of softies and LPS in a small tank. Carbon and water changes may help if your corals are fighting -- if you do a 25% wc, run carbon and everything opens back up you might want to consider using carbon regularly (or 24/7) to keep the toxins at bay.

I have done two 5 gallon water changes since the corals started closing up. I initially thought it might have been allelopathy but I was running BRS Rox carbon at the time. Also, the leather frag is tiny... maybe only a little more than 1/2" tall. The other corals are spread out quite far apart from each other. About a week ago I removed the carbon since it wasn't having any positive effects and I thought the water might have been too clean for the corals. There have been no changes since then.

[rcypert]

Just think about what happened in the last two weeks. Did you add a new fish or coral. Did you change foods. Did you bomb your whole house with bug killer. Did you start spraying your dog with flea med and playing with him before touching your tank. Did you add new rock to the tank. There could be many things.

[RA]

Most of the corals you mentioned cannot take high lighting. Move a coral or 2 to where they are getting less light and see if they do better.