It's possible that there is still air trapped in the filter since you recently cleaned it. Unplug the power cord and watch and see if any air bubbles rise up the output line, wait a couple minutes and plug the power cord back in. Watch the output flow to see if it has improved. You can also try tilting the canister a bit to see if any more air escapes from the filter.
If the above suggestions don't work for improving the filter flow, you will probably have to take the filter back apart and check that everything is in the correct position and try again. Don't forget to properly prime the filter with water before plugging the power cord back in to the wall outlet.