Welcome to TRT, Donna Marie!
I'm glad you've come here for help and advice - please know that we only want what's best for your creatures and for you, so hopefully you won't interpret our offerings of advice as harsh.
I'd respectfully suggest that before you buy anything else, purchase a copy of
Bob Fenner's The Consciencious Marine Aquarist. Much of what you are being told here will be explained in greater detail.
For a new hobbyist I don't suggest starting with anything smaller than a 20-30 gallon tank. Small water volume is harder to keep consistent. We maintain a 1 gallon nano tank in our shop and it takes daily care and tweaking - and not for beginners. Tank has one fish, 2 shrimp and a couple of tiny
coral frags... but I digress.
If the store you're dealing with doesn't take back returns on things they shouldn't have sold you in the first place, then I suggest you don't shop with them anymore. I own a brick and mortar aquatics store and it rots my socks when retailers do people wrongly like that then refuse to correct the situation.
Find another shop to help you out, or find another local hobbyist to help you out.
I don't suggest keeping more than 2 of the same species of clown in most tanks unless they are very large tanks. 2 juveniles will become a male/female pair and will usually show aggression to others. Mixing species of clown in a small tank isn't a good idea either for the same reason - they will compete with each other for territory and usually there's a winner or winners and loser or losers. The store who sold these fish should know this
5 fish total in a 30 is pushing the envelope as it is... please don't add any more. Please make sure that the water is being tested and parameters being correctly maintained. Care of saltwater fishes isn't rocket science but it does take some common sense and a lot of patience.
Hope this helps,
Jenn
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Member of the "J" Crowd & the BRW Crowd!
LFS Owner:
Imagine Ocean

Just keep skimming, just keep skimming, just keep skimming, skimming skimming! What do we do? We skim, skim, skim!