How can I get a guppy out from beneath an under gravel filter?

Question

I have a small tank with an under gravel filter.

At some point, a guppy fry managed to swim down the circulation tube (while the bubbles were going full blast) and set up house in the cavity between the gravel and the bottom glass of the tank.

I see him (it's a he) from time to time.

Although he seems fine, and is even growing normally, I'd like him to rejoin the rest of the fish in the "over world".

I can't take the circulation tube off without gravel filling the "under world". I don't want to turn the bubbles off (now a power head) for too long.

How might I get resurrect him?

Answer 1

Does your under gravel filter system have two uplift tubes?

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I would try completely uncovering one of the tubes while reversing the powerhead flow on the other. The ambient current should provide sufficient opportunity for the guppy to swim up the other uplift tube and out into the tank.

You may have to give it a bit of time. You won't likely be able to supply enough back pressure to actually "blow" him clear across the aquarium, but if he finds his way close enough to the other tube, the current should be enough to coax him to find his way out on his own.

Answer 2

Next time you are doing a partial water change, take your discharge hose and siphon your water up through the uplift tube. That should provide enough suction to effectively "vacuum" up that little guy into your waste water. The bigger the hose, the better because the faster water flow will increase your chances of catching him. It may take a few tries, but you'll get him eventually. But make sure you are collecting the water into a bucket or some other container so you don't accidentally discharge your fish down the drain.

Answer 3

Now that you're using a powerhead, I'm assuming that is keeping the guppy from getting past the top of the lift tube and out into the tank.

Try removing the powerhead and snaking just an air hose down the uplift tube and let the circulation resume using just the stream of bubbles from the bare tube. That should provide enough circulation (temporarily) to keep the filtration going, but still provide enough room (and current) to suck that little guy up the tube and out into the tank… eventually.