Bro, your 4 footer is not ready to add in any fishes for the time being although already ran for a week. You need to cultivate the bacteria in your tank first before the kick off. Getting LR and adding a sump tank will be idea.
$40-70 can get very beautiful fishes such as emperor, blueface, regal,small queen, small french, blueline, majestic, etc. Seems to me that u intend to keep less than 5 angels in your tank. Then I would recommend a small queen. Sealife and LCK currently having small size queen which might be slightly above your budget.
Sponge is definitely a very good food for angels but not all angels like sponge.