Hi there, I have jus bought an ek d5 pump, and an Alphacool brass pump top with 3 inlets and 3 outlets. Neither the pump or pump top came with an o ring to seal the two, so I purchased a generic on ring that fits, however when I connect the two, the pump does not seem to seat too well. When I run the pump I don’t get a good flow rate. Could the o ring be too thick for the two units?