Tetra Pond Aquasafe Dechlorinator (250ML, 500ML, 1L) Filter Media They provide some surface area

They provide some surface area for bacterial colonization but this is actually very limited

Rekord 110

on which the smallest model has one and the two larger ones both have two individually adjustable air outlets

250ml treats 5000 US Gallons (approx 19000 litres)

Tetra Pond Aquasafe Dechlorinator (250ML, 500ML, 1L) Filter Media They provide some surface areaMakes tap water safe for fish by removing harmful compounds and adding beneficial substances. Contains special compounds that eliminate chlorine and chloramine, and bind up heavy metals. Contains colloids that coat the fish, protecting them against infectionUnlike most water conditioners, AquaSafe leaves no residues and is completely broken down to harmless substancesApplication Add 50ml of Tetra Pond AquaSafe to every 1000 litres (220 gallons) of