How many ways is the suction split ? Are there valves ? Main drains connected in the skimmer pot or at the equipment pad ? Do you have a spa ? Got pics of the equipment and pool ?
If you have more than one skimmer, plug the second with a tennis ball or appropriate rubber pipe plug.
Insert the hose directly into the suction port, don't use a vac-plate, especially if the skimmer used is also used for the main drain.
Use a skimmer closest to the pump.
I have a 16 by 32 unground pool with cartridge filter ( Pentair pump) 2 years old. I vacuum using a hose connected via the closest skimmer. The other skimmer is turned off. The suction from the skimmer is now significantly less than before. I have emptied the filter baskets and cleaned the cartridge filter. The suction is still low. What other actions can I take?
If you have a main drain, is that closed while the skimmer is open? But we are all flying blind here. Post some pics of the pool equipment from various angles so it can all be seen.
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