you may want to look at troublefreepool.com to get some assistance on your water chemistry needs.

Save your money and drain it. We drain do about 3-4 of these a week in so cal right now and it is far cheaper to go this route. Drain, power wash, chlorine wash, clean the filter and refill. Around here the average job is $500-$800. Sounds like a lot but you'll spend half of that in chems and you bought a house as is so you may want the entire shell inspected at that time as you never saw it in the first place.

repair guy - do you have problems in socal with pool sheels popping out of the ground. In areas with high water tables (Houston) there is some risk of that with draining the pool.

Check the weather, plan, and make the whole thing a 4 day job. You can run all that junk through your filter and cleaner if you want to but its going to mean that you have to clean those out once or twice but in my opinion....thats actually more work. Your probably going to have to do that once anyway as it is.

I would hire a professional. You got some good advice about how much it would cost in chemicals to clean it up, and that doesn't include the "gotta look at it, but you can't use it" factor with our hot summer coming up, especially if you have kids.

Also, if you just treat it chemically, that won't address any issues it may have with equipment not working properly.

I'd hire a professional to inspect it, clean it up, stabilize and maintain it for a couple of months (thru the summer, maybe?), and then think about taking it over yourself.

SueinTexas
...former green pool in CA owner...

Assuming your mechanical sytem is functional. You can have that pool sparkling with about $100.00 in bleach and a couple of days of pretty hard labor. Let us know if you want ot go that route and we'll help.

No water table issues here unless on the coast. Yes, it can be done with a lot of chlorine and real hard labor but if you want to be done quickly, direct application of chlorine on the shell is quickest. Here's the scenario in a foreclosure so you can't really use the common thought on clean up if you can't even see 12" into the water. These houses sit for close to a year or more. They went green and the county forced a drain early on in the process. House gets picked up by an agent after the bank takes possession. A listing occurs and the pool has to be filled to make things pretty. Offers fall away, pool goes green again. That pool has had so much dry time that you come along and treat it chemically for a hundred or more, and that's conservative, and then you find all kids of pretty cracks and waterline marks that you could have dealt with if you just drained it in the first place, water table permitting. i've found the strangest thing under that water on foreclosures. The stove, the pool heater, the pump and filter, mounds of dog doo doo. People get cranky when you tell them to leave their house.