I purchased a Tetra 77848 and some standard 1/4" ID tubing to aerate my wort. However, there's an issue with the tubing hooking up to the output on the tetra, it's too narrow for the 1/4" tubing. I rigged the tetra by wrapping it with some electrical tape to make it thicker, but it tends to come pop off while I'm aerating. Is there a good way to attach this tubing to the air pump?
I wasn't able to find a good spec sheet for that pump, but a comment somewhere said the outlet is 1/8" (and that is typical), so 1/4" tubing is quite a bit larger than you want.
When aerating wort, you shouldn't really be needing much pressure, giving you some room for creativity when making this connection. You'll just need something better connection than electrical tape.
One choice: go to your local auto parts store and find some vacuum line adapters. You might find a 1/8-1/4 adapter, which would be perfect. Or you might find a thing with a hose barb on one end and cone on the other. This is meant for temporary connections to vacuum, but should be OK for this.
Another way: Get a bit of 1/8" tubing and shove it inside the 1/4". Then shove the two layers of tubing over the outlet of the pump. This won't really be secure until some kind of clamp is added. A small spring clamp (again from your local auto supply) would work, or a zip tie pulled tightly over the two tubes. BTW, this type of tube-to-tube connection will require a metal tube in the inside to prevent collapse, so make the joint right on the pump outlet, not somewhere downstream.
Yet another way: you might find a sanitary filter to be a useful hose adapter, with bonus of cleaning the air going into your wort. This oddly familiar setup shows how such a filter might be used. Finding a filter with that accepts 1/8" and 1/4" tubing might take some digging, but they are out there.