I want to try a ATS on my new setup. (48x30x20) 125 gallon with a 40 breeder sump. I'm guessing about 125 gallons of water. Question 1) what size should my screen be? 2) How much flow GPH? I am new at this, I believe ATS do work and I'm cycling a new tank
The current guideline is roughly based on how much you feed, on an average daily basis. Water volume is a secondary factor, but really only when the tanks get large IMO (like 250g or more) So, try to estimate your daily feeding regimen. The basis of measurement used for screen sizing is the "cube" - like an Ocean Nutrition size cube (roughly 2.5-3 cc's)
from my understanding 1 square inch screen per gallon. so correct me if I'm wrong, I did 125 divided by 1" would be a 12.1/2" screen right?
No, that's the old guideline. The new guideline is based on feeding. 12 sq in of screen, lit on both sides, for every cube of food fed per day, or equivalent thereof. The 1 sq in/gallon rule fell by the wayside to the feeding guideline about 3 years ago.
...but to answer your question about the old rule, if you had a 125g tank, you would have needed 125 sq in of screen. So a 12" x 10" screen. By the feeding guideline, I would use a minimum 2 cube/day scrubber (that's 24 sq in) and if you feed a lot, probably a 4 cube/day screen, or larger. But, I would not use a screen that is much more than double the size compared to what you feed. So, how much do you feed? Break it down if you want - there are some rough conversion factors for converting pellet, nori, etc...
