I have surprise fry in one of my tanks (I've counted 8 or 9 so far).
I've removed all the adults into a separate tank, so the fry won't be eaten.
I have apple snails in the tank as well. These guys create a lot of waste.
I've removed the filters so that the fry don't get sucked into it. I can't use a sponge filter because the snails eat it. Now I have waste accumulating on the substrate. I don't want to vacuum it, because I don't want to suck the fry out.
I can't remove the fry from the tank to clean, because they're difficult to see and I could not be sure that I got them all.
What other methods are there that I can use to remove the waste?