Connecting Tanks


How to?

I have a 55 gallon Tank and a 10 gallon tank. My 55 gallon tank is a community tank and I would like to connect the water flow with my 10 gallon tank and use it as a hatchery/breading tank. I it easier to maintain the water parameters on a big tank than a little one so I was wanting to connect their water, so in essence it is one big tank in two places.

I have two ideas on how I could achieve this, but I was hoping there was already an established method.

idea 1. Drill 3-4 holes at the water line of my big tank, seal water lines in those holes and have the water lines drain into my smaller tank, kind of like a over flow system. Then have a pump in the little tank that would pump the water back to the big tank.

idea 2. Find a pump(s) that would have the exact same flow rate pump the water from one tank to the other and back. They must have the exact same flow rate as to not over flow one tank and drain the other.

Any other ideas or methods that already exist? Drilling would be a simpler setup, but I am iffy about drilling holes in glass.


setup one tank lower than the other, so you have a siphone effect. have the larger tank as the lower tank, and the siphon input set to a height where if it were to run your tank low, it wouldnt overflow the other. then set a return pump, with a level switch (cheap on ebay, or other places) that simply return the water that has siphoned off.

Look into a referigium (can't remember how they spell it). copying that kind of setup may also work for you. I don't think you need to drill holes, unless you intend to have the fish swim between the tanks.


Thought #2 will not work trust me. either though they are the same gph the Head height will lower the return pumps out put. and the pump going from the 55 to 10 will go faster than its rated dur to the siphon effect


you could use to under water power heads like the ones used in water falls for ponds and stuff,
60gph pums are usually 13$ at petsmart


Maybe this will be of help:

I have just completed building some fry tanks that have one filter to clean all four tanks. This is how it works:

Tank 1, top LH drains into tank 2, top RH through 22mm pipe, Tank 2 drains into tank 3, bottom RH through drainage built into the end wall, tank 3 drains into tank 4, bottom LH through 22mm pipe, water is then pumped through a powerhead filter back to tank 1. Using large bore pipe ensures adequate flow through, avoiding the need for switches or pump controls. Syphons have a nasty habit of moving too much water too quickly or stopping completely if the intake comes out of the water at any time. The large bore pipe is just an overflow, not a syphon.

Your option 1 is probably the best to go for, but ask your local glass company if they could drill the hole for you.


You can avoid drilling the tanks by using a pvc "bridge" to connect them. Provided the water level is the same height in both tanks, you could simply hook up a powerhead in the smaller tank with the outflow running through a tube (clear vinyl would work well) into the larger tank. The pvc "bridge" would maintain the water level between the tanks, basically acting like the intake on a hob filter. You would want to screen the ends with something to prevent fish from traveling between tanks...

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