Cloudy Water

[BigDave]

Power Powder is Calcium Hypochlorite and will add to your calcium hardness. Aylad suspects that calcium is part of your trouble so it's probably best to use Sodium Hypochlorite (aka bleach, liquid chlorine) to chlorinate the pool. Since you've experienced FC of 0 lately your cloud may also be an algae bloom starting.

Do you know your CYA level? You're going to need a good testkit, we recommend the Taylor K-2006 (accept no substitutes!). It can only be found online - if you order through the Amazon links on the How to Get the Right Testkits for your Pool the Pool Forum will get a few scheckels for sending you there. While waiting for your K-2006 (you have ordered it, right?), you can see if your local wall mart carries the HTH 6-way drops kit (check availability). If they do, pick one up, it is compatible with the Taylor K-2006 and will let you measure CYA.

[Watermom]

If your Walmart does not have the HTH 6-Way kit (not test strips though), at least pick up a cheap OTO/Phenol Red kit (yellow and red drops) to use while you wait on the good Taylor K-2006 kit to arrive.

[PoolDoc]

Using the soda ash is likely causing the problem; stop it. Use borax instead (20 Mule Team borax from the detergent section)

+ We routinely recommend the use of 20 Mule Team borax INSTEAD of soda ash, for several reasons. It's cheaper than pH plus (soda ash labeled for pools) but more importantly, it does not raise your alkalinity much, and does not combine with calcium to cloud your pool. The way to add is it is to pour it into your skimmer SLOWLY, while the pump is running. (How slowly? Slowly enough that it doesn't make a big pile in the bottom.)

Borax also can help control algae, but you have to add a LOT. It ends up costing around $50 per 10,000 gallons of pool water, for borax and muriatic acid, if you buy your borax at Walmart and your muriatic acid at Lowes. Soda ash is now frequently available at Walmart in the detergent section, at prices MUCH cheaper than the pool prices for the same chemical. If you ALSO need to raise your alkalinity, you can buy that instead. But if your alkalintiy is high enough, and you only need to raise your pH, it's better to use borax:

20 Mule Team Borax @ Walmart
Arm & Hammer Super Washing Soda @ Walmart
Muriatic acid @ Lowes (do not get the 'safer' muriatic acid; do read the "Using Muriatic Acid" sticky)