I've used HTH algaecide - do I need to drain my pool?

[PoolDoc]

Kem-Tek dichlor 2 lbs @ Amazon => ~$6.50/lb (Jul 2013)
Kem-Tek dichlor 5 lbs @ Amazon => ~$4.50/lb (Jul 2013)
Kem-Tek dichlor 12 lbs @ Amazon => ~$4.00/lb (Jul 2013)
Kem-Tek dichlor 22 lbs @ Amazon => ~$3.60/lb (Jul 2013)

Looks like they are out of stock on the 22#, so the 12# is the largest you can get.

Two other options:
+ I think you may be able to get a 1x trial membership at Sams -- call and ask.
+ Home Depot sometimes carries the KemTek brand. But, Kemtek now makes dichlor goop, too. So if you want to check out Home Depot, print the pictures from Amazon, and make sure what you buy is EXACTLY the same.

Hm-mh, Kem-Tek has updated some of it's labels, and I found a picture on Costco, so apparently Costco may carry this in some parts of the US, though not here. Anyhow, here's their current (Aug 2013) label:


If you decide to get dichlor from any other source, you probably want to post EXACT brand and product name here first: about 90% of the sold now is some sort of goop mixture.