I would concur with the AP test kit. My gf has the 5 in 1 for her 10 gallon and it's much less accurate than my AP kit, especially once the strips have been exposed to the air. I was informed at PetSmart that they regularly practice matching web prices to in-store prices. Go now because I was told the 13.49 price is temporary because they are clearing out the old cardboard packing to the 'new' plastic packaging which is a little more expensive. They should still match the price on the new kit with that price though, at least they did for me. Plus the price per test is much cheaper than the test strips when using the vial/drops method.