Just a heads up: 11lbs of dichlor into 27K gal should give you 24 ppm CYA. But check the Costco dichlor, and make SURE it's undiluted (55% or 61% available chlorine). If it is, you might want to use the dichlor to raise your CYA, rather than buying CYA.

Dichlor, at $2.50/lb (Sams Club price) = $5/lb as stabilizer without considering chlorine. But hard-to-dissolve HTH (or other brand) stabilizer is often sold at $5/lb or MORE. When you consider that a pound of dichlor has about the same chlorine as a $2 0.75 gallon jug of Walmart bleach . . . using dichlor is a very cheap and easy way to add BOTH chlorine and stabilizer.

The primary CAUTION here is that this applies to pure undiluted dichlor, purchased at a good price. That rules out most Lowes, KMart, Walmart and pool store offerings. It also rules out Costco in MY area, but apparently their stock varies from store to store.

The secondary CAUTION is that this "good deal" ONLY applies while you still NEED stabilizer. Using dichlor, after you have enough, chlorine may be an OK deal, but once your near the "TOO MUCH" level, dichlor is a "bad deal"