I seem to have somewhat of a problem. Here's what happened last Thursday:
My 29 gal was in need of a water change (it had been 2 weeks) and I was going on a long weekend vacation on Friday. Now normally I would mix the saltwater about 2 days in advance, but I didn't have the time, so I mixed it and allowed it to set for about 2 hours. I used my remaining RO/DI water and filled the other half with tap water (which I have done many times before with absolutely no ill-effects and I treat it with a chlorine/chloramine remover that I've used many times) and let it sit for about 2 hours. Then I topped it off with a cup of boiling water to match the temp (and match the S.G.).
I added it to the tank and all seemed well, but I came back a few hours later and my Blastomussa polyps had retracted. I thought it was strange and they were still retracted on Friday afternoon! I came back today (Sunday) and 3 days later they are still retracted! I haven't noticed any color changes, but they're definitely retracted tightly. Everything else seems fine.
Does anyone have any resources, help, or suggestions? This is my first ever issue with corals, I didn't buy the corals, they were hitchhikers, but seemed to be doing well! I haven't done anything yet because I don't want to screw anything up, but i've spent a little while doing some research on the internet but there's not much on this species.
Here's the tech stuff:
fluval cannister filter (I rinse the sponge weekly, at the same time as the water changes)
2 percula clowns (doing great)
Coralife Aqualight T-5 lighting
650 total GPH flowing through the tank
82 degrees (i'll probably be lowering that though)
a few small aptasia near the polyps
possibly a peanut worm