Look up the problem in the troubleshooting guide in the user manual.
Check the filter media, if it is dirty, the flow rate will be lower. Depending on the type of filter media (cartridge, sand, fiber balls), either clean it, flush it, wash it or replace it with a new one.
Check that the hoses have no holes.
Check for loose clamps.
Check that there is no air at any point in the circuit. If the filter pump is aerated, it must be vented according to the instructions in the user manual.
The water flow in the filter pump is not as strong as it used to be. What should I do?
The water flow in the filter pump is not as strong as it used to be. What should I do?