Fluval Underwater Filter U4 (130-240L) Dog Tins & Pouches a standard sodium thiosulfate dechlorinator

a standard sodium thiosulfate dechlorinator is not enough

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

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Fluval Pre-Filter is designed to capture solid waste before they reach other media

Add 50ml of Tetra Pond AquaSafe to every 1000 litres (220 gallons) of water

Fluval Underwater Filter U4 (130-240L) Dog Tins & Pouches a standard sodium thiosulfate dechlorinatorFluval Underwater Filter U3 (90 150L) The Fluval U Series are underwater filters that offers outstanding 3 stage filtration, increased water movement and vital aeration. Fluval U Series internal filters are the perfect solution where external filtration is not possible. Complete and efficient 3 stage filtration, including BIOMAX biological filtering Ideal for fresh, marine and reptile environments. Now with new and improved design features!