Glass CO2 Drop Checker – CO2 Monitor Kit for Aquarium Tank – Functional and Reliable – Transparent Drop Checker, 4dkh/pH Reagent Solution and Suction Cup

Like the title worked great and looked great. Till I need to move it. Snapped right at the right bend

The drop checker was extremely easy to use, I just added the liquid inside flipped it over and pushed it into my tank. It took an hour or so for the color to change and stabilize itself to the CO2 in my tank. This is perfect for tanks that was to measure their CO2 to make sure their plants are provided with the nutrition they need to grow. Not only that but it helps you control the algae growth in the tank by knowing how much CO2 is in there.One thing to note is that if you have a tank smaller than 3 gallons, it will a lot of the space. I currently have this in my 2 gallon tank and it is very obvious and cannot be hidden as well, but considering the pros it brings this is nothing.

This Glass Co2 drop checker is a valuable tool to have in your tank. It's small and being glass it basically disappears in the tank and is NOT conspicuous. The monitor fluid goes from blue to green when the CO2 levels are proper and with a planted tank now that drop checker REALLY disappears! The drop checker has helped me several times as I was injecting too much CO2 so the green went yellow and even to clear once. I shut my CO2 generator down a day or two and the monitoring fluid went back to green and I turned the CO2 generator back on turning that needle valve down to about one bubble per second. Finally I got the needle valve to where the drop checker was green every day which is where you want to be. Do you ABSOLUTELY need this? No. But for me, it was quite helpful and I'm glad i bought it. Glad I'm using it. On a side note, I notice that in photos of a lot of really high-end Amano type tanks I see these little CO2 drop checkers so I figure if THEY are using them perhaps it would be wise that I use them as well.

Works great, but like all suction cups it finally failed to suction over many many months. Just be ready to replace the suction cup as needed, and it's good to go. I only needed this for initial testing of my diy CO2 system to get an idea of the CO2 max and min when I first set up my system, through several months to test CO2 production by yeast in various temperature seasons. Once I had that down this wasn't necessary for long term use anyway, but definitely lasted long enough for initial calibration needs over a 6-9 month or more duration👍

Easy setup

Update: 2022-12-14: I got two replacement suction cups - This means I don't have to toss the drop checker. It's back in the tank and working perfectly. FYI, trying to use heat with the old suction cup doesn't work. Just ask for a replacement. Their customer service is great!Update: 2022-12-08: I wrote support and they are sending me a replacement suction cup! If you need a replacement, reach out to them.I think it's a good piece of glass - and works... I mean it's just glass, so why wouldn't it. Three years later the suction cup is hard as a brick and useless and it won't adhere to the side of the tank. Using a little silicone lubricant doesn't help even if the glass has been cleaned. Ideally, we'd be able to buy suction cups to keep using this vs making it a disposable object that adds to the planet's trash and makes us spend more.

A really well-designed drop checker, and it fits nicely in my 10-gallon tank.I was afraid it would be big and ugly, but it looks good, and I can always hide it somewhere in the tank.It comes with a solution (already premixed), so you don’t need to do anything—just put some drops in, and you’re good to go.The color changes are really noticeable; green and blue look truly different, so now my shrimp are safe

Glass came in fine and product worked for my CO2, however the liquid was at half when I opened the package and it looked to be spilled at some point. Liquid had spill marks but it was fairly dry so I don't think it was from this shipment.

My only gripe is that the accompanying CO2 detecting liquid could have been more