Low skimmer suction

Hi all-just bought house that came with very dirty pool (emptied several garbage bags of leaves from pool bottom).
Now I'm in the process of getting the chemicals worked out. I can see the bottom of the pool in the shallow end, but not the deep. The main problem I think I have is that the suction is very low in both skimmers. I can't imagine the pool chemicals getting circulated properly with such low skimmer suction. I can get decent suction in one skimmer when I close two of the valves, otherwise when all valves are open, suction seems low. I've snaked and used pool hose with bladder thing in both skimmers-pump and also from pump to skimmers. I do see small fizz bubbles out of return jets and plan to replace o-ring in pump. I have a SAnd dollar SD-80 filter. The pressure gauge, which does go to zero when off, runs at around 20-22psi, and only goes down to 18psi after backwashing. Is this a sign that the sand may need to be replaced? Would new sand make the skimmers work better? I have tried running filter on recirculate, which only improved skimmer suction a little. This is my first pool and need all the help I can get. Thanks!

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It sounds like the problem may be in your piping or returns. If your piping is too small, there's little you can do, without a major pool re-build. But you can check for things that may be fixable:

1. Examine your pool eyeballs. Some pool owners think it's important to have the return stream of water 'ruffle' the surface a lot, and install tiny eyeball orifices to create a high pressure -- but low flow -- return jet. Removing the eyeball orifice will allow you to test and see if this is the problem. If it is, you may want to get a larger orifice nozzle and use it to replace the one you have.

2. Look to see if you have an undersize or restricted valve.

3. Look to see if you have a Hayward inline tablet feeder -- these restrict flow tremendously and should be removed on any pool over 10,000 gallons.

4. Take pictures and post them using Picasa, Webshots, Flickr or whatever, and we may be able to make other suggestions.