Shrimp sump tank?

[Khuligirl93]

I've recently set up a 20g high tech planted tank, and I've been toying with the idea of putting a smaller tank underneath it just for shrimp. I was thinking either a 2.5 or 5 gallon and just continuously siphoning water through airline tubing from the 20 down into it, and then get a tiny pump to pump water back up. That way it can feed off of the ferts and CO2 of the larger tank, and I only have to do 1 water change.
Only problem I'm running into in my hypothetical plan is how to make sure the water siphons down and gets pumped back up at exactly the same rate, so I don't end up with either an overflowing or an empty shrimp tank.
Has anyone done this before, or have any ideas??

I'd prefer to keep it simple and cheap, and not get a gate valve or anything like you'd use on an actual sump.
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[nirbhao]

Does the tank have to be below? If you can set it up so that the two waterlines are even, you won't need a pump at all. Look in to communicating vessels.

the tiny computer is full of delicion!

 

[GreenThumb]

It's called a Refugium...

What you're talking about is making the smaller tank into a refugium type setup. You've got the right idea about the water path, and also the right instinct that it could over flow one of the tanks if it isn't set up right and that would be a bad day.

Google refugiums. Freshwater folks do them all the time.

You need to have a safety measure in the large upper tank to make sure that the water will never rise above a certain level. Some people use overflow boxes mounted on the inside of the tank like here: https://www.toofishy.com/In-Tank-Overflow-Box-with-Single-1-Bulkhead-7-x6-x2.html

The flat side faces the inside the tank and has teeth to help prevent getting clogged with floating plants and other debri. The tube passes through a hole in the tank and attaches to tubing that sends the water down to the lower tank. A pump in the lower pushes water back into the upper tank. So you'd have to drill a hole in the tank or have someone else do it.

There are also "hang on tank" overflow boxes, but research them well as I've heard they can stop working and cause an overflow under the right conditions.

You can also use a stack pipe, and some folks have diyed 'hang on the tank' overflow pipes like this one:

Time to do some reading up on plumbing!

You'd probably have to set up a light for the lower tank so it could use the ferts and co2. Otherwise you might get algae....

 

[Khuligirl93]

Yes, unfortunately below the existing tank is the only place I have room

 

[Khuligirl93]

Sorry GreenThumb, didn't see your post before.
Yeah.. I was hoping there might be a simpler solution. I don't think I want to get into all of that right now. Thanks for the info though!