I bought a house just recently with a seriously neglected inground 20x40 vinyl-lined pool. It has tenants (last count were 7 turtles, 1 water moccasin, and tadpoles galore) and the water is dark green/black. The liner and pump appear to be in good shape.

I can only imagine how much mud and leaves are inhabiting the bottom. We are considering converting from chlorine to a salt-water/saline pool.

Please excuse my ignorance because I may not be asking the right questions, AKA any advice would be appreciated in the matter:

1. It's been suggested that I pump the water/mud out and start with fresh water, but others say that is ill-advised because it is a vinyl-lined pool and would collapse without the water to hold the walls up. Which is best? Pumping seems so much easier.

2. Once I have dredged/pumped the pool, should I do the salt-water/saline conversion at that time or wait until I have chlorinated it considering the bio-matter involved (dead animals, algae, etc.)?

3. I've had several people suggest aluminum sulfate as a cheaper alternative to get all of the algae killed and to the bottom for dredging/pumping instead of expensive flocculants and chlorine shock. Has anyone ever tried or heard about this?

serendipity pools

Ok - first off DO NOT drain your pool or you just bought yourself a new liner (at best) or had your pool walls and slopes collapse (worst case)

If you want to get some of the water out, you may pump down to only 6" or so left in the shallow end. Any more than this and the liner will lose is position on the slopes and either rip, shrink, shatter or wrinkle - all of which are bad. My advice is to leave the water in and do the following:

The first step is to remove all plant and animal material from the pool using a large leaf net on the end of your pole. Get as much as you can by dredging the bottom being sure not to have any sharp items like screws sticking out of the end of your pole / brush.

Get everything that you can and then leave it for a few hours or overnight to have the material settle to the bottom again. Then repeat process.

Once you have most of the material out of the pool you will want to begin a chlorine shock process. After the first shock or two you will notice the water become much clearer. Ideally you will have the system running to circulate the water properly. If not, you must manually agitate the water to ensure the chlorine gets dispersed and does not sit, concentrated, on the liner itself as it will burn the color out of it. If you do run your system be sure to backwash your filter OFTEN to make help get rid of all the plant material.

Once you have completed these steps you pool will be almost clear. Likely the water will clear somewhat and then remain cloudy which will be result of the algae that you have. Regular chlorine will not clear this up, so at this stage you will begin an algicide and vacuum process for your pool. It's a lot of work, but swimming is great so get to it!

I hope this information is helpful.

Steve Goodale
Serendipity Pools & Artificial Rock
Vancouver, BC
604-421-8429
1-888-267-0802