I want to start a 36 gallon corner as my first marine tank. I would like to put a 10 gallon sump in the stand.
What do I need?
I have a pump but I know very little about it. It is made by Little Giant and seems powerful, but what do I know about pumps? I found it in a bag of old aquarium stuff.
Can I make a basic sump with just a tube with a syphon sending water into a ten gallon and then the pump I have putting the water back into the tank?
Nope... the pump will pump at the same rate, until it gets grungy, or impeded by something OR is torqued down with a ball valve or other valve of sorts. You need to ensure that your overflow is designed/built and rated for a compatible gallons per hour to match your pump.
Water will overflow or siphon from an overflow tube/box into the sump. The pump will send it back up to the tank. If the pump is super strong, and outcompetes the overflow box/siphon whatever... you will overflow your display tank.
If the pump is underpowered as compared to the overflow, your sump will overflow until it gets to the point of breaking siphon, or emptying an overflow box.
Dave is right, you need to match your overflow and pump. Be sure to use an actual overflow, not just a piece of tubing as a siphon. An overflow will not only skim the surface of the water, but also help prevent your sump overflowing by breaking the siphon when the water in the display tank gets too low.
So I will need an overflow? I was hoping I could get by with just a tube or some PVC pipe.
And because I need to know the power of my pump, I need to buy a new one?
I would very strongly reccomend you use an overflow. Depending on what overflow you buy, and what pump you have you may be fine. We can probably figure out the GPH rating if you tell us what pump you have. The good thing about using an overflow, is it will help balance out the overflow/return cycle. Partricularly if the pump is rated under what the overflow is. The overflow works by siphoning out water that spills over into the overflow box, so as water is pumped into the tank, it overflows the surface skimmer, into the overflow box in the tank and is siphoned out. It's much harder to flood either the tank or sump using one.
An overflow need not be a box either. If you can get the tank drilled, you can do something like this:
Though, in my opinion, if you drill, and go through that trouble, you should build an overflow box. They are much more efficient at surface skimming. They are NOT hard to build and install. Here's one I just built:
Then you can drill the bottom (if not tempered) or side and build a durso stand pipe. I drilled the lower side on this tank:
The strainer and elbow inside the tank, flow to the external pipe outside. I made the pipe tall-ish and drilled with an air hole to stop the "slurping". It then flows down to the sump below. The black fitting you see in the forefront is a return nozzle.
For what it's worth, this is the sump underneath. It's just 4 gallons, but allows me to put the heater, skimmer, etc. below the tank. It also allows me to dose kalk or whatever I need to do, and keep it from causing huge swings in the display.
Eventually, the tank that will sit in the place of the bowfront, will be plumbed through the floor into the 75G sump in the basement.
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