OK, first off if the weights are not sealed algae will grow inside. I used to empty my stair weights weekly and add 60% algaecide inside. There is not flow thru the weights. I would pull the stairs bi-weekly and brush under & behind them. Easier to do from the deck. I also added smaller holes in the sides to "promote" more flow thru them. Red rectangles OEM holes, Yellow circles my holes. Smaller so little kids can't get their hands stuck.
I did not have a mat or suction cups on the bottom. I also dumped the pea gravel in my weights yearly and washed the new pea gravel in a chlorine solution. Picture below is stairs out and weights draining/drained.
And I second what kim said about keeping the bottom smooth. 16 years with the same liner, just sun faded with gin clear water.
& see if u can find replacement parts for those steps once u figure out what kind they are.
www.innovaplas.com
