[Monkey]

im doing some research for a friend, he has a 39 gallon (180litres UK) tank, Salt Water fish and live rock, he wants to fit a sump to the tank.

ive read alot of threads on here and are very helpful

correct me if im wrong, but we remove all filters, skimmer, heater etc from the main tank and put them in to the sump, the only things that go in to the tank is the pipe that feeds the sump and the pipe that comes from the sump.

all filters etc are in the sump cleaning and heating the water before it goes back in to the main tank. salt, chemicals etc (i know nothnig about fish) then get introduced into the sump and not the main tank

where im getting stumpped its how much turn over of water is needed to be able to match the syphon overflow and pump for the main tank.

if the sump is big enough can fish (sea horses) go in to the sump permenantly?

or can it be used to introduce other life, (corel, new fish etc) in to the main tank

[volitan_fa]

All of your equipment (save the lights of course) can go into a sump. You can put in a refugium partition in your sump, but I would recommend using a separate QT for adding inhabitants. If that particular addition is diseased it will infect your whole tank if it's in the sump.

To match the flow rate you need to find out how much your overflow is (gph) and match it with a pump of the same. You can install valves in the lines to adjust the flow rate if need be.

[Monkey]

thanks for your reply, ive heard that a turn over of water being 20 time the full amount of the tank per hour, so thats about 800GPH, that sounds like alot. is this correct?

[volitan_fa]

Actually that sounds about right. 1200gph isn't that uncommon to see either, but that would be quite a lot in a 39 gal tank.

[Monkey]

ok thanks,

slightly different question,

im having a hard time understanding how an overflow syphon works, i can understand the capperlery type action from getting the water from the comparment in the tank in to the rear compartment, but whats stopping the overflow from over filling the rear compartment.

i know that if the pump fails the water level will drop to under the level when the overflow can fill up, but what if the overflow pipe gets blocked for some reason, the water in the tank wont drop and the overflow will keep filling. but is there something in its design that will stop this if it happens