A 70' long x 30' wide x 4.5' deep is a large lagoon/pond. Basically big enough you could house most requiems available to a private aquarist. Except for the ponds depth.
Still - if you looking for something local that you could possible keep in a pool with average depth of 4.5' and with Atlantic Stingrays. Then I would suggesting stick with small requiems sharks - like Atlantic Sharpnose, and the Bonnethead.
Still - if you looking for something local that you could possible keep in a pool with average depth of 4.5' and with Atlantic Stingrays. Then I would suggesting stick with small requiems sharks - like Atlantic Sharpnose, and the Bonnethead.