Two pH tests, dramatically different results.

[Minawri]

I was just doing my weekly checking of the water parameters for my 55g cichlid tank. I was using the API strip test. Everything was in check except for the PH, which is showing up at less than 6.0. So I broke out my API test tube pH kit... and the test is reading at 7.6!

What could make my tests read out so differently? I haven't added anything to my tank except a bit of aquarium salt to treat a scrape my severum got trying to squeeze into a slate cave he is much too large for.

I tested twice and the strips keep telling me less than 6.0 and the test tube keeps reading at 7.6. Both test kits are fairly new.

Gonna do a big water change, but still curious as to what could cause this and how I could get an accurate reading.

 

[James_in_MN]

Strip tests are notoriously inaccurate. What you need to do is go buy the API Freshwater Liquid Test Kit. It runs for around $30-32 at the chain pet stores around my area.

 

[AquaOne]

+1 James, the best accuracy is liquid testing. If the price-tag is a bit much, you should at least have the ph kit and nitrite kit.