Applying acid to suspected calcium scale
Hey guys!

(were my ears burning

...?)
First I just want to remind everyone that Muriatic Acid is not a toy and can cause burns, blindness, and the fumes can make you feel really bad! Please take all reasonable precautions when dealing with it including, but not limited to, rubber gloves, long sleeves, eye protection, good ventilation and keep a container of water on hand to immediately rinse anything that gets splashed with the acid!! :!: (anyone have more acid precautions? bring 'em on!! - keeping things safe must always be in the forefront! :angel: )
If all that's required is getting a straight dose of MA onto a suspect area while it's still underwater - I have a couple of ideas;
1. Get a pressurized pump sprayer from the hardware store (one of the pesticide 'pump up' sprayers), the acid is a little harsh on the metal parts but they're fairly inexpensive and the acid doesn't have to be in there too long. Find an area you want to test that's within 'wand reach' from the deck and pump up the sprayer and pull the trigger. (you won't see the bubbling that Jason mentioned, but it should be enough to strip the calcium from the area. If the area is shallow enough to reach, a turkey baster can be used.
2. This one is a little more 'risque'/ dangerous and I doubt that anyone but I would even try it, but I offer it just in case... Fill a balloon with acid, using a plastic funnel, like a water balloon, rinse the balloon thoroughly!! and tie it off (rinse it because you probably won't be able to tie it off with the gloves on) Now attach what's left of the fill opening on the balloon to your pool pole, secure it with a rubber band, and force it down over one of the stains and use the open ended pole to pop the balloon. Instant acid treatment to one small area!
OK, you say you want to see it 'bubble and fizz' -- Secure a regular tea or tablespoon to a pole and scrape the suspect area with the spoon (the spoon needs to be tightly secured as it will take a little effort to scrape some off) Now GENTLY!! retrieve the spoon, if it's calcium and you removed it from the pool slowly enough, there should be some of the suspect matter still on the spoon. Transfer the stuff from the spoon into a plastic container and pour a couple drops of acid on it -- make sure that the container is upwind of you - remember about the fumes!
Now for the big dirty little secret... feel the walls below the waterline, if they feel bumpy, like little grains of sand were on them, look at them closely and see if you can see what looks like 'clear/ amber grains of sand' sticking to the wall. Calcium is usually precipitated on the entire pool surface but only really noticeable in the areas where it's worst. If you can discern the bumps, you can scrape and test as per above.
That's about what I can come up with for now. Even if these are impractical for you, mayhaps they'll spark some input from someone else. We're here for you Vonda and will be until the problem is resolved!