15 assorted fancy guppies in a 10-gallon tank!
Any recommendations will be greatly appreciated. Thanks!
I use something similar to these on my tanks. Wire filter guard.If you use a hob or a canister you can put fine mesh over the intake to reduce losses as well, but you're going to have to rinse it frequently, depending on how much particulate builds up because it will slow the filter.
One more add to this about the plastic mesh and to give a picture of what is looks like. In addition to protecting fry/shrimp from HOB and cannister intakes, it can also protect them from a power head.The pre-filter sponges work, though as others say, depending on how clean your tank is, they can get clogged easily. They also take up space. With a 10G you don't have much space to begin with, so a sponge filter or a sponge pre-filter over an intake of a HOB is probably not ideal. The sponge pre-filters come in different sizes. The smallest clog the quickest. Larger ones (you can search "pond filters") will allow much better flow but they use a lot of space (e.g. 3-4" in diameter)
For the lowest profile shrimp/fry guard possible, I used this plastic mesh and zip ties to slip over the intakes of my cannisters. It would work for a HOB too. The mesh is normally used for wires but it works really well for this! It's inert, thin unlike a giant sponge, and even lower profile than the metal cages. It comes in several diameters.
Here's my post about it