Hello, this is my second season with the pool. I have a 25,000 gallon vinyl in ground pool with a salt water generator (I am located on Long Island, NY if you need that info too...aka by New York City). I have used this site for many things. I bought the chemical test kit recommended and do all the test myself. I also use the pool calculator app so my readings are pretty much always where they should be. Last fall, the company that put the pool in installed and covered the pool since we also bought the looploc safety cover. They supposedly put winterization chemicals in but I was not around when they closed it so I don't know if they actually did or not. When the pool was opened in the spring it was extremely green with a lot of leaves in it even though there were no leaves when it was closed. We definitely need water bags to hold the cover down during windy days to prevent the leaf situation, but I was wondering what I should add chemically to try to prevent it from opening green. I have read your articles about how to close the pool but some people say to use the algicide, some don't. I've had people recommend the closing kits but they don't use swgs and the pool store told me to just use liquid shock. So, needless to say I'm not sure which direction to go in. Any suggestions would be greatly appreciated. Thanks in advance!!!