DonnoBBD, The best cheap media that I've found is nylon baler twine. You can pickup a 20,000 ft spool at TSC for about 20 bucks. Take a long serrated knife and saw thru the spool lengthwise and you end up with a whole lot of short pieces. Fill up a barrel or IBC with it and you've got a very good bio filter. The black boxes are very pricey but being gone all week forces them. The big trick is getting the solids out early before they dissolve. I never had much luck with a swirl filter but the best thing I used before the RDF was a sieve. It had a 300 micron screen and was really very effective. There's a guy on youtube that goes by mrsuperb1 that has some pretty good vidoes on building one if you don't want to spend the cash to buy one. The main piece of advice I can give if you just want a FUN father son project would be to keep the stocking density LOW. 25 fish in a 275 gallon tank is FUN. Above that it becomes WORK. Above 50 becomes a full time job, HA Good Luck, Steve.
