The use of trichlor tabs doesn't contribute to too high TA levels--it's CYA levels you have to worry about with a feeder. Trichlor tabs also are very acidic, so most folks have to make sure that they don't drive the pH too low, but that doesn't sound like a problem for your pool
Here's the method for lowering TA:
http://www.poolsolutions.com/gd/lowe...p-by-step.html
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