Review on 🐠 Efficient XY-380 Large Pond Filtration Sponge Filter for Fish Tanks & Aquariums: Water & Wood's Biochemical Solution by Kathleen Roy

I bought 2 a year or two ago and put them in a 65 gallon aquarium with a Fluval 406 filter The next day the water smelled bad and my fish were under a lot of stress . I removed two sponge filters and they smelled very strange. I took out the sponges and started cooking them in a large pot. As a result of boiling, the water turned red, similar to the color of gear oil. For two hours I drained the boiled water, squeezed the filter tightly, poured water again, boiled it and so on until the boiled water became clear. Since then there have been no problems. I recommend letting them cook well before using.