The TF-50 differs from the standard TF-100 in several important aspects:
It does contain the very useful FAS/DPD chlorine test just like its big brother but only contains 1 oz of 0871 reagent instead of 2oz .....therefore you can expect about half the number of tests...probably around 40. It does not include a separate cylinder for testing the FAS/DPD as found in the TF-100. There is one cylinder for use with all tests.
It also contains the tests for Calcium Hardness and Total Alkalinity.
The CYA test contains 2oz instead of 8oz found in theTF-100....enough for 3 full tests.
It does NOT contain the OTO chlorine test and (this is important) it assumes you already have a pH test. If you do not already own a pH test, this kit may not be a good value for you. That said, you can always go to WalMart or a Pool Store and buy an inexpensive pH and OTO tester (around 5-10 dollars) and your needs will be complete.
The idea behind this test kit is to provide you the very highest quality test results at an economical price.
Many of the members at www.Troublefreepool.com will be happy to answer any detailed questions you may have.