I use CoralRX. You're correct re brown-jelly, and honestly I don't know if CRX will get it, but I've not personally seen the problem recently. Try to avoid bruises, bumps, and look for heads that are nicely extended all around the disc, nothing that's weeping brown stuff or contracted for no apparent reason. It grows pretty fast, if happy. Likes fairly strong light, wants to be generally upright. Don't subject any living thing you want to survive to hydrogen peroxide...it's good at killing stuff off rock, but avoid even the bubbles from a dipped rock hitting one of your corals. Problem with a 72 day qt for a coral is light: they can starve during that time, since it's light that provides their sugars. I don't like to buy from shops that stock sale fish (though they may keep some permanent fish) in the same tank with their corals, because that's a prime way a coral could come in with a fishy parasite. I like the coral tank sumps to be separate, and for the water dipped for a coral sale bag to be only from the coral tanks, not from the sale-fish next door. That way I've honestly never had a coral come in with a fishy problem.