I guess you could also create a frame to cross a whole section of a bio clarification tank. 12in wide wide 3 feet across by 3 feet deep just be sure to make it fit tightly using silicone or other sealer, so as you pump water out of the bio clarification tank it draws water only through the filter. Use stiff netting type material on each side fill with shredded Mylar and other plastics learning to pack it to the right density will benefit. make an outer frame siliconed to the tank and an inner frames to slide into place with rubber making the seal tight and making it easier to remove for cleaning
It is a way we can take and use materials normally going to fill a land fill and recycling them to filter biomass from our water. you can also set it up and let water free fall by gravity through a bio filter and it would also airiate the water at the same time.
I was researching the bio filter that a lot of companies sell and what I found was the material is nothing more that fibered spun plastics with just fancy names to make you think it was something special. I figured I could recycle Mylar snack bags and do just as well.
be careful using asorbic acid types of Vitamin C it will lower your pH so be sure to always test your water seems 6.5-7.0 pH does well for most plants