normal to stay closed up?

83 is pretty hot, but 79 is fine. i woudl guess it is probalby shedding. they will "shed" every few weeks where they close up and a mucusy film will come off. a little more flow can help get it off and get yoru toadstool back to normal. it is possible there is osmethign else wrong, but i woudl guess this is what it is because it is perfectly normal and i have talked to a lot of people who saw it and thought it was acting sickly or soemething. id give it a few days and see if it gets better :)
 
FWIW, you don't want to drop the temperature too fast. The corals you showed won't care too much, but some other don't like rapid changes. You didn't specify how fast "as soon as possible" was, but ideally temperature changes that large should be over several hours. Just a tip. I've found that corals in general don't like rapid changes, even if it's for the better. I lost several heads on a trumpet coral because I dropped phosphate too quickly once.
 
i'll keep that in mind... the temp was dropped over several hours by putting a bag of ice in the filter area of the bio-cube. then the sun went down - which helps a pile cause the tank is in the sun room... i'm finding it hard to keep the temp down out there with no blinds on the windows. even with the a/c at 79 and the ceiling fan on high the tank still gets up around 83 on sunny days.
 
you have to keep in mind though, yes, the outside room temp is 79, but the tank is goign to be hotter. usualy, water is cooler than air because of evaporation... but if you have one in a closed top with some hot lights over it like in the biocube, you arent going to get the tank as cool.
also, your heater may be off by a bit. i'd check that too :)
 
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