To use, rinse off the stone with chlorine-free water, soak overnight and add to your tank, preferably near an air source. If you have an airstone, place it near the airstone. EcoBio-Stones are sized according to the volume of your tank. Once immersed in water, beneficial bacteria in the stone will start to propagate and disperse into the water approximately every 30 minutes. Depending on the size and condition of your tank, it will normally take from 2 to 4 weeks to see results. However, it can be as short as two days and as long as 3 months (very rare). If medication is necessary to treat sick fish, either remove the fish or the block until treatment is completed. The bacteria in EcoBio-Stones are viable at pH 3 - 11 and at temperatures of 50 degrees F to 149 degrees F. The most effective water temperatures are from 77 degrees F to 140 degrees F.
Extra blocks may be necessary depending on variations in the condition of water, temperature and amount of fish. No need to add liquid or powder bacteria.