What makes a good reservoir?

ive got 4 of the ones with diamond patterns and none of them leak

Both of mine did but $5 on some epoxy and a few hours to let it dry, i just flipped it over and filled the holes at each corner. works fine now

i use 30gal rubbermaid totes.
but i only fill them with about 15-20 gallon max.

I've recently bought a cheap 110litre plastic storage box to use as a res. I've had no problems with leaks, but I've doubled it up just in case. They only cost me £11.00 each.