As
@jamesdomini4 said, regular IO salt is OK, but reef crystal IO salt is better.
I will probably switch to the reef crystals after my bucket of regular IO runs out.
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My plan is to call my LFS tomorrow and ask for a refund/replacement.
Should I ask for a refund? Or a different torch?
I would ask for a replacement, and if they don’t have any others, then a refund/store credit. The problem with getting a replacement is that it’s likely be just as fresh a cut. If they do have another make sure that it was cut at least an inch below the polyp/where the coral’s flesh stops and make sure that it isn’t cut through the polyp like this one was (it was probably several heads that were really close together and they cut between them, but they cut the side off this polyp - people do this all the time, and in an established aquarium that the colony is already acclimated to, it’d most likely be okay, I have a Duncan that was cut like this, and its just fine - though Duncans are more forgiving than torches).
As far as regular IO, I’ve found that it’s consistently low in calcium and magnesium and a little higher in alkalinity than I prefer. Your corals will live and grow in it, but they’d probably do better in a different salt. If you’re looking for a good, reasonably priced salt, I’d recommend Fritz’ RPM. Also, keeping your tank at 80° is completely fine, even 82° is fine, I keep mine around 79.5°.
Personally, if I were you, I’d hold off on buying any more corals until you’ve got alk, cal, nitrate, and phosphate test kits. Or at least any stony corals (including LPS). Your tank is still very new and isn’t stable (I set up my current tank in Jan, and I wouldn’t consider it stable yet), you need to understand and stabilize your alk, cal, and nutrients, which just isn’t possible in such a young tank (with the nutrients especially, it’s going to take time to mature and settle, especially using dry rock, my tank is going through an issue with nitrates right now, despite very little feeding, and doing water changes twice a week, they’re at like 60ppm, I blame running GFO and using 2/3 dry rock).
Its a shame about your torch, but if your lfs is any good, they’ll make it right. But this is a good lesson to thoroughly inspect corals/frags before purchasing.