HOB filters sometimes suck fry into them. And depending on how fast you find them, they might die. I'm posting 2 pics for you. If you want, you can try one of these two methods. 1. Stick the blue filter over the intake of the HOB, but I'm not sure the fry won't stick to it. 2. Make a cheap sponge filter by adding a piece of air tubing and airstone, with heater suction cup to hold to tank.
I got a box of 2 from a chain pet store CHEAP. They come with carbon in them. Dump out about half the carbon. Stuff the tube, ect, down in it. KEEP the lil round piece of filter that's in the top. Cut it half way through, the. Stuff it around the tube to help hold the tube in. Steal a lil good bacteria from an existing filter to seed it. Keep up WC and testing for a few weeks to make sure the seeding is working fine. After the meds are gone, dump the carbon out. Carbon releases what's collected back into the water around the 6 week mark.
