<a href=showthread.php?s=&postid=14272443#post14272443 target=_blank>Originally posted</a> by kelso1980
ok...let's start at square one: how much flow SHOULD i have? 55g and 20g sump. The sump will be ~ 10 feet below the top of the tank.
I had a nano (no pump needed) and then when I bought my tank, a pump came with it so there was no need for research. Is there an informational website that you guys should direct me to so you dont have to explain it all?
There are varying opinions out there and I cannot debate the points of view other than mine. I keep a VERY low GPH going thru my sump. This is because I believe the SUMP is where all of the "good stuff" happens, like skimming, carbon reactor, phosphate reactors, refuge, and additional live rock, etc. Therefore, I do not want the water flying past the "cleaning system" at top speeds, but rather going down dirty and coming back clean.. I run mine at about 400gph, which is about 4x the DT volume. Even people who seem to subscribe to my school of thought find 400gph low, but so far it's working very, very well. (check back in 10yrs for some real data... until then it's a theory)
This also implies that your return lines will not be adequate for your in-tank circulation, you need (again in my opinion) 30-50x turnover in your DT to keep the detrius and other stuff suspended, and raised to flow out of the DT into the sump (where your filter-sock catches the big junk, and you change that every 1-3days as required)
My DT will have 44x circulation once the pumps arrive next week. I also run mainly SPS, so I want super-high flow more than most, and i also want super-clean, nutrient poor water.. My Nitrate and Phospate have been 0 for 2 months, and i believe they will stay there... its the goal.
Anyhow, if I had your setup, I would be looking at 300gph or 400gph turn over, but I'd try to even get it set-back at about 200 gph just to see for a few months.. my bet is the result will be positive.
You're currently looking at aquiring a pump, so i think it would be wise to get a pump that is over-sized by 50% of your target GPH. so for my way of doing things that would be a pump that could deliver 1000gph at head-pressure... Then you can pull-back the volume (using a ball valve) and divert water into fuges, reactors, etc with some of the over-pressure...
One note, if you use the over-pressure to create additonal flow in your DT by way of adding new return-pipes, you're increasing the GPH in the DT, and subsequently adding more GPH thru your "cleaning system" sump.
Now, I did not write all this to start a debate, I'm kind of hoping someone of a different school of thought will post below to give you multiple points of view.. if this was my home-town fish-forum id be blasted about 8 ways to sunday for posting this "low flow thru the sump idea"... but what can I say... I follow my own flag. (and the idea came from reading on RC, I didn't invent nutthn here)
LOL!
