They should be ok for a day or two. You could float the filter media in the tank for now. Do you have an air pump running? That would help with flow and aeration.
I like Aquaclear filters. The Aquaclear 50 would work for your tank. I use that in my 35 gallon tall hex tank. If you get this filter, be sure to tilt it very slightly toward the tank as these filters, if not tilted could cause water to seep outside the tank if the media gets excessively clogged. Replace the included carbon bag with a sponge . Using filter floss for additional filtration is optional but I use floss. I buy it in a large roll from Big Al's and cut as needed. I throw out the clogged floss when servicing the filter every two or three weeks and just rinse the sponge in removed tank water.