How should One & Only be added to the aquaria?

Before adding One & Only to your tank, make sure the water has been dechlorinated. Research has shown that One & Only can be safely used with DrTim’s Aquatics’ AquaCleanse tapwater detoxifier. Other dechlorinators can be used but some are actually harmful to One & Only: do not use any product that contains aldehydes in its formula. UV-sterilizers and protein skimmers should be turned off before adding One & Only and remain off for 36-48 hours after dosing.

It is important to shake the bottle well before adding One & Only. If you see only a clear liquid you have not shaken One & Only well enough. Pour the One & Only over the biological filter media in your biofilter. If you do not have dedicated filter media it is fine to pour the liquid into the fish tank water.