Rated 1.2 out of 5 by 9
Rated 3 out of 5 by mangomon It works fine once you figure it out
As per other reviews, the instructions leave a lot to be desired, but after doing a search for Azoo CO2 indicator I found a Youtube video that will explain everything. There is no commentary, just a short video explanation on set up. What the video doesn't tell you is that it takes at least an hour or two to get a some what accurate reading. The color you see at first set up will change as things settle in, give it time. One other thing, to extend the life and make it easier to take apart and put back together, put a very thin film of silicon grease on the O-ring or should I say square-ring. You should be using this on all your O-rings.
May 22, 2014
Rated 1 out of 5 by Verified Reviewer Doesn't stay on glass!
Should have read the reviews...I guess you get what you pay for. It seems like it's very easy to use but the stupid thing won't stay stuck to the glass for more than 5 in. I cleaned the glass before attaching it.
July 23, 2015
Rated 1 out of 5 by Spritely Bad Suction Cup
I'm sure this thing would work just fine if the suction cup would actually hold it to the glass. The thing falls off a few minutes after I attach it. Every single time. If someone has a tip for making a weak suction cup work better, that'd be super helpful. Also, the directions ought to be more detailed.
January 13, 2015
Rated 1 out of 5 by James007 Worthless
Didn't work out the box. leaked into aquarium. Replaced O-Ring with new one and worked once. Would not use if it was free. Junk
March 25, 2014