You do NOT need CYA between 50-100. Too high and creates a whole new set of problems. This is gonna be really difficult with test strips. I hope you'll be able to get a good kit. At the very least for now, can you go to a reputable pool store and ask them to test the water including CYA. Just don't let them talk you into buying a bunch of stuff.

For now, don't add any more shock until we find out what your CYA level actually is. Just use bleach for your source of chlorine. Like I said above, without good numbers it is hard to help. Until you can get some better numbers, just do this:

-- Go to Walmart and get a cheap OTO/Phenol Red kit (yellow and red drops).
-- Every evening, add 1.5 gallons of plain, unscented 6% bleach unless your chlorine is really dark yellow. In that case, just add a quart or two.
-- Also, run your pump 24/7 and backwash as needed.
-- Test your pH and post results.

Don't worry about having your chlorine up to 10ppm right now. With algae, it won't stay there long. Also, ignore the bromine reading. This is a chlorine pool.

Hope this helps. I'd like to be able to help you a little more accurately, but without a good kit, it is very difficult.