If you use canister or HOB filters (or any filter that employs sponge or floss type media), you know that you can purchase additional or replacement sponges and floss from your filter's manufacturer or your LFS. Whether it's a Fluval, Aqueon, Eheim, SunSun, Sicce, Marineland, or another brand, sponges and pre-cut floss pads are often available to replace what is included with your filter purchase.
However, if you're like me, you buy your own sponge and floss in bulk and cut them to fit your various filters. To ensure that I always have these sponge media ready to go, I will often cut multiple copies and store them. To make this process easy, I simply create a template using a piece of cardboard. For canister filters with media trays, I outline a tray on the cardboard, then cut the cardboard template out. I then use the cardboard template on the sponge sheet, etc.
Depending on the filtration you use as well as the number of tanks that you maintain, this can be an economical approach to media replacement. Futhermore, buying your sponge or floss this way gives you greater media flexibility (e.g., thickness, PPI density).
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