Can I backflush and recharge my filter without taking it apart?
Yes. Take filter to kitchen or laundry faucet. Remove U-tubes from hose. Attach exhaust hose to faucet. Run water back through filter to flush out debris, shaking jar several times to loosen dirt.
Remove exhaust tube from faucet and put intake hose on faucet to fill jar 1/2 full. Replace U-tubes. Take filter back to aquarium, put intake and exhaust tubes in tank. Make sure strainers face away from each other. Plug in filter, turn it on and turn the jar upside down for a few seconds to get the prime going, then set upright.
Submerge a plastic container into the aquarium and put the intake and exhaust tubes into the container, such as a tea pitcher. Lift the container with the two tubes inside high enough to get the top above the water's surface. At this point, you will be running the filter only on the water in the small container. You may add the Diatom powder directly into the container while the filter continues to run. A minimum powder charge for the "XL" Diatom is about 3 cups and for the "D-1" Diatom, 1 cup.
Naturally the more powder you add to the system the better the filter will perform.
When all the powder has been absorbed into the filter and the water in the
small container is running clear you may carefully lower the container out from under the pickup tubes.