Hey guys, I’m working on a 135g build and just wanted to get some additional opinions on overflow size and return pump options before drilling the tank. From what I understand the general rule is 5-10x turnover for the overflow size but I’ve gotten some advice from 1200gph minimum up to a max up to 2400gph. I was originally going to use a HOB overflow but undersized it and it didn’t look good on the tank. I have also purchased a current eflux 3170 gph DC pump as it was on sale and figured it could handle whatever overflow I end up getting without running at 100%. I’m look at modular marine overflow boxes as I have read and heard good things but I am just a little confused and conflicted on what size would be best I’m leaning the 2400gph just to be safe and running the pump at around 2000gph maybe or going with the 1800gph to save money if that will be enough? The tank is 6 ft long and the sump is a sapphire CR44 from trigger systems. Let me know, thanks!
