Hey guys, I have a small challenge for you. In your opinion what would be the best way to boost biofiltration (or beneficial bacteria) with just $75 on Amazon.ca. I got a $75 amazon gift card from my aunt but I can think pf nothing I'd want to invest it on other than my tank. I want to boost my biofiltration but I'm still stuck on simple small sponge filters (which would help but I still have money left over!). Thanks for reading!