65 gal

hi, thank you for reading. i am back on the horse with my sump build. i have a 15 gal sump 21x10x18 (space constraint) using a eshopps pf 300 over flow, 2 baffles, and a rio 2100 return with a 4ft head using 3/4'' return line. my question, my eshopps 300 has a 1 1/2" bulk head. do i need to...

yes i am building a sump, i found a tank that could fit my stand due to a divider in the middle of the stand the previous owner installed i had to go with a small tank. 20x10x18 i think 16gal, so my space is very limmited. dose anyone have advice on how far apart the baffles need to be? and if i...