you are going to need a heater with or without lights.
if you shop around, you can get good deals at local stores from time to time. so, don't go by what you see to be the going price. i just got a 2 inch hippo for 27.95 at a local store, and i traded in some of my overgrown macroalgae for store credit so it ended up costing me 4 dollars!
someone chime in here if i am way off, but i would just buy regular reef sand and not "live" sand. you will have the live rock for the tank cycle and bacteria. i think that is a needless expense. the sand will turn live eventually.
if you are undecided about a tank size, your best bet is to go with the largest you can afford to keep.
that hippo tang you want will get massive, so choose the tank accordingly.
i don't think it's harder to keep a young tang alive. i bought my tangs small also.
never had a pistol shrimp, so i can't comment on those.
don't forget to add a 160 gallon bucket of instant ocean salt, which is around 30 bucks, and consider all the other "odds and ends" we never seem to calculate in the bottom line. nets, various containers for this and that...(i guess you could use moms tupperware
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