Hi and Welcome Tia and Compooler.

Tia, you have been "Pool-Stored"--you have a problem and you give them a TON of money and they HAPPILY sell you all kinds of useless chemicals.
You are right to be suspicious: "Chlorine Lock" was invented by pool companies to explain why they had you use Chlorine pucks far longer than you should have. It means your CYA, ie stabilizer is at a far higher than it should be, and that it SEEMS that the chlorine level you are maintaining it with cannot cure it.

This is wrong. As for Compooler, a level of 60-90ppm for stabilizer MAY be correct, but also may not be. It's usually the recommended range for people who use a saltwater generator to generate their chlorine. I usually keep mine much lower, between 30 and 50ppm, yet another moderator, aylad, keeps hers at between 80 and 90ppm. Who is right? We BOTH are!

I live in North Central NJ and aylad lives in Louisiana and the climate and our pool conditions require different levels. If I was there I'd do EXACTLY as she does and if she was here, she'd do what I do.

Chlorine isn't just used by sunlight and algae. It's the main sanitizer and algaecide you use in your pool. Mostly, it's the ONLY algaecide I use in my pool. But it kills bugs, bacteria, viruses, metabolizes oils, urea, even sun-tan lotion. But it's most important function is to kill the bacteria that exists in fecal matter, in everything from bird poop, to the microscopic amount every person brings into your pool.

However, if you have lots of UV rays or lots of algae, the chlorine gets consumed by those, leaving none for the unpleasant, but critical function of sanitizing your water to prevent waterborne diseases.

OK, so where does this leave us/you?

First, you need post a set of proper test figures. You can have the pool store test it for you (they owe you big time so you don't have to buy anything in return). $500 for a 25,000 gallon pool in chems in one month is outrageous and we will try to help make sure that NEVER happens again!
Have them test
FC (Free Chlorine)
CC (Combined Chloramine)
or
TC (Total Chlorine)
pH (measure of acidity/alkalinity)
TA (Total Alkalinity...not exactly what it sounds like)
CYA (Cyunaric Acid, or Stabilizer/Conditioner)
CH (Calcium Hardness)

You've told us your pool is 25,000 gallons, but we need to know if the pool is vinyl or tile/plaster/concrete/etc. What kind of pump and filter you have.
Do you have a heater or salt water generator ?
What have you been putting in your pool? Not the label but the ingredients. You said you put two pounds of chlorine in (not much) but was that
Tri-chlor...
Di-Chlor
Calcium hypochorite 48%, 68%?
Lithium hypochlorite?

You added a phosphate remover (creates goop and not needed). Which one?

Algaecide? What are the contents (Copper or ammonia multiple ingredients: bad, Single ingredient 60% Poly...something: good)
Clarifiers, Bluing, etc?

You'll need a proper test kit. For the moment there's an inexpensive 6 way (I think) drop test kit at WalMart. But you should invest the $50 to $70 in a proper Taylor K-2006 kit. Go to the link on PoolDoc, Watermom or aylad's signature and click on it to get it from Amato. It helps support the forum. It's also the best investment besides time that you will make in your pool over the next,,,well, forever!

We believe in keeping things simple, at least to start. Most of the pool chems you need are at your grocery store, not at the pool store, and much cheaper.

The biggie is bleach. Regular unscented 6% bleach. Each gallon will raise your measured chlorine level by about 2.4 ppm (parts per million, the standard).
We use bleach for chlorine
Borax (20 Mule Team) to raise pH
Muriatic Acid (from Home Depot) to lower pH
Baking Soda (Arm&Hammer) to raise TA.

Only CYA has to be gotten from a pool store or from the pool section in places like WalMart or KMart.

Bleach, Borax, Baking soda...We call it the "B-B-B Method" of pool care. Simple. Easy. Cheap. Effective. Very Effective.

Finally, you should go to our sister site, Poolsolutions.com and read the tips and hints there. It takes about an hour or two and is pretty much the foundation of what we'll tell you when we see your pool test numbers.

Carl