Review on 🌊 EcoBio-Block EBSNC00107 Coral Nano Water Clarifier - 1.125x1.125 Inch (Pack of 1) by Emma Santos

They work great when used properly. The idea here is to create a bacterial culture in your aquarium. Chlorine kills bacteria. Tap water contains chlorine. If you have used tap water, bacteria will not grow and your aquarium will remain cloudy. I use filtered tap water. Also, your tank will be foggy for the first week or two after that, especially if you have live plants like bacteria and nitrate-producing plants. A filter and bowl will help get them out of the water column, so be patient. My 3 gallon tank lasted 6 months without needing to be cleaned. I just keep refilling it with fresh water as it evaporates and change the filter every month. They work great. My freshwater plants love them and so do my fish.