For the longest time my pool suffered from Low Suction and low pressure.
This summer I finally decided to get dirty and solve this problem once and all.
Calling a pool maintenance for troubleshooting is out of the question, they are TOO EXPENSIVE and they charge by the minute they are there troubleshooting!!
So, with google in hand I searched and searched, finally I found a post in this forum that was the only thing I had not tried so far, opening the pump and checking the impeller.
After removing the impeller a quick visual inspection didn't show anything out of the ordinary. I was disappointed at first because I was already thinking, "another troubleshooting work going to waste".
Then it occurred to me to place the impeller under the water tap with the water flow feeding the center and expecting to see water coming out of the side openings... to my dismay, I only see water coming out a little through one of the openings!!
I got a wire hanger and made a quick tool to get it through the openings... and here we go !! all kind of gunk, little dust, leaves, bugs, small stones started to come out while pushing them with my "special" tool !! one by one I cleaned all the holes and tried the water test again, this time water flowed cleanly through all holes. Very excited I proceeded to assemble the impeller and the pump again. Turned it on and after priming it.... Got excellent suction and pressure now !!! the water in my pool is moving like it has not moved in years !! the waterfall from the spa is falling nicely and the vacuum runs like crazy !!! It happened that the basket right before the pump was broken allowing for all kind of debris to get inside the impeller.
I just wanted to post this in case I can help anybody to fix the mysterious "suction was good last year and now is not" symptom.