Fill the pump basket with water.

That’s the quickest fix. Turn off the pump, open the lid, fill the basket completely with a hose, close it, then open the air bleed valve on the filter. Turn the pump back on and water should start flowing. If it doesn’t, you might have a clog or a suction-side air leak.

Most loss of suction is just trapped air. The pump can’t pull water if it’s full of air, so manually filling the basket forces the air out. If you have a multi-speed pump, run it on low speed first — high speed can cavitate and refuse to prime. Let it run a few minutes with the bleed valve open until a steady stream of water comes out, then close it.

If this happens repeatedly, check the pump lid O-ring and the drain plug. A tiny crack or a loose fitting will suck air and make you prime it every time. Also check the skimmer basket and weir — sometimes a stuck weir door blocks water flow.

Don’t run it dry for more than 30 seconds or you’ll fry the mechanical seal. That’s a much more expensive fix.