Fluval U4 Poly/Clearmax Filter Cartridge

Replace 1 Poly/Carbon cartridge every 2 weeks.

Do not replace all filtration cartridges at the same time. Alternate filter cartridge changes so that some older cartridges remain in use. This ensures the re-seeding of beneficial bacteria, so that colonies discarded with older cartridges will be replaced by vigorous new ones. To enhance bacterial action, pour a dose of biological aquarium supplement onto your filter cartridges each time you change the media.

• Unplug the power cord.

• Open the filter cover (To make the operation easier and in case the filter is positioned under an aquarium frame, tilt the filter forward until it stops but make sure there is enough electrical cord to allow the filter to pull forward).

• Slide the foam cartridge frames out of the filter body. Keeping them vertical to avoid releasing the debris collected inside the debris receptacle. Place them in an empty bucket.

• Remove the poly/carbon cartridge from the cartridge frame.

• Remove the foam. Rinse the debris receptacle and the foam pads using water taken from the aquarium or replace one of the foams following the recommended replacement schedule. Do not use tap water as this will kill the beneficial bacteria in your foam. Note: Never use soap or detergents as these products could be harmful to the inhabitants of your aquarium.

• Replace the foam pad. Make sure the foam is positioned behind the tabs on the sides of the frame.

• With the carbon side facing out, re-insert the poly/carbon cartridge by inserting the lower end of the cartridge into the lower end of the cartridge frame then snapping the top side of the cartridge under the two tabs on the top side of the frame. Do not press too hard, as the cartridge must sit on the top of the tabs on the sides of the frame. Hint: For best results replace 1 poly/carbon cartridge every 2 weeks.

• Slide the BioMAX cartridge out and place it in the sink or bucket.

• Pull open the tab on the side of the cartridge, opening the cover. Rinse the BioMAX with aquarium water, never tap water, or replace half the quantity every 5-6 months. Never replace all the BioMAX nodes at one time, as valuable colonies of beneficial bacteria would be lost.

• After rinsing, put the BioMAX back in cartridge and close the cover. For best results completely fill the cartridge with BioMAX nodes but allow the cover to close easily.

• Re-insert foam cartridge frames into the filter with the poly/carbon pad facing inwards. Re-insert the BIOMAX cartridge into the filter making sure to properly align the hole at the bottom of the cartridge directly on the top of the impeller opening.

• Close the filter cover and if required snap the filter body back into position on the filter bracket.