Review on 🐠 Brightwell Aquatics Xport BIO Cubes - Highly Porous Bio Filter Media for Optimal Filtration in Marine and Freshwater Fish Tanks by Latasha Hayes

I only use this when my engineer Bull gets a feather up his ass and decides to fix the tank whether I like it or not. The guy is just an idiot! Anyway, I put charcoal and about ten of these blocks in a media bag and I would say clean water within two to three days. I'll take out the charcoal and leave the cubes to the good bacteria for a few months. I've never had a problem with the tank (other than that nasty unagi tenant) and all the other fish are happy. However, I recommend a media bag to place them in as the blocks will soften after a month or so.