FZONE Aquatic CO2 Glass Drop Checker PH Momitor for Aquarium Plant Fish Tank Test CO2 Kit
$12.99
Price: $12.99
(as of Oct 15, 2025 19:27:40 UTC – Details)
From the brand
Fzone studio
Fzone started in 2018 as a neccesity to find aquarium products that were from the best quality while still being beautiful and accesible. It started as a hobby, but we noticed the expenses and realized that the aquarium market was in need of help.
We appreciate all the support that we’ve received from our customers. Thank your for supporting us, and we hope you continue around to grow with us.
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Package Dimensions : 4.92 x 3.39 x 1.46 inches; 2.39 ounces
Item model number : CO2-Testkit
Date First Available : October 28, 2019
Manufacturer : FZONE
ASIN : B07YCQ77JJ
Best Sellers Rank: #13,282 in Pet Supplies (See Top 100 in Pet Supplies) #15 in Aquarium Test Kits
Customer Reviews: 4.4 4.4 out of 5 stars 640 ratings var dpAcrHasRegisteredArcLinkClickAction; P.when(‘A’, ‘ready’).execute(function(A) { if (dpAcrHasRegisteredArcLinkClickAction !== true) { dpAcrHasRegisteredArcLinkClickAction = true; A.declarative( ‘acrLink-click-metrics’, ‘click’, { “allowLinkDefault”: true }, function (event) { if (window.ue) { ue.count(“acrLinkClickCount”, (ue.count(“acrLinkClickCount”) || 0) + 1); } } ); } }); P.when(‘A’, ‘cf’).execute(function(A) { A.declarative(‘acrStarsLink-click-metrics’, ‘click’, { “allowLinkDefault” : true }, function(event){ if(window.ue) { ue.count(“acrStarsLinkWithPopoverClickCount”, (ue.count(“acrStarsLinkWithPopoverClickCount”) || 0) + 1); } }); });
Superior glass CO2 Drop Checker with the most accurate and reliable 4dKH solution in the market
Quick and easy to setup. Simply fill the drop checker with the provided solution to half full, affix the checker to the glass, check back in one hour later for accurate reading
Providing easy to read CO2 level. BLUE = Needs more CO2. GREEN = Sufficient CO2. YELLOW = Danger! Too much CO2. Constantly monitoring the CO2 level in the water column
Complete kit for monitoring CO2 contents. Package include 15ml 4dKH/PH solution. 1 piece CO2 drop checker, 1 piece suction cup.
Customers say
Customers find the CO2 drop checker reliable and easy to use, with the included reagent working well. Moreover, the product helps control CO2 levels in aquariums and offers good value. However, the color change feature receives mixed feedback, with several customers reporting zero solution color change. Additionally, durability is a concern as customers mention the glass can break easily.
13 reviews for FZONE Aquatic CO2 Glass Drop Checker PH Momitor for Aquarium Plant Fish Tank Test CO2 Kit
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Jack –
It works for me
As an aquarium enthusiast, I’m always on the lookout for new tools and accessories to help me maintain a healthy and thriving tank. The FZONE Aquatic CO2 Glass Drop Checker is a recent addition to my collection, and I’m very impressed with its performance so far.The drop checker is designed to help monitor the levels of CO2 in your aquarium, which is crucial for the health of your aquatic plants and fish. It’s easy to install and comes with clear instructions, making it accessible even for beginners.What I appreciate most about this drop checker is its accuracy. It provides a clear and easy-to-read reading of the CO2 levels in my tank, which helps me make informed decisions about how much CO2 to add or adjust. The glass construction is also very durable and high-quality, so I don’t have to worry about it breaking or cracking easily.One thing to note is that the drop checker does require some initial calibration to ensure accurate readings. This may take some trial and error, but once you have it set up correctly, it’s very reliable.Overall, I would highly recommend the FZONE Aquatic CO2 Glass Drop Checker to any aquarium owner looking for an effective and reliable way to monitor CO2 levels in their tank. It’s a great investment that can help you maintain a healthy and thriving aquatic environment for your plants and fish.
Amazon Customer –
Easy to use
Its simple to use, a good indicator for high tech tanks. Helps me keep my tank in safe parameters
Michael Ki –
Helps control how much CO2 I use.
I use this to dial in the amount of CO2 for my planted tank. It’s easy to use and looks kinda cool in the tank.
Tim Parks –
Great little drop checker!
Very nice. Well made, and the included reagent works like a charm. Great value as always from Fzone!
T. Tozawa –
Easy pH check
If youâre running an CO2 system, this is a great way to quickly check pH to make sure everything is on the up and up. Filling the round chamber with the solution is a bit tricky as I had to angle it in weird ways to get it all into the round chamber. I tested it against an API pH test and it seems to match up fine.
H3AVYTR00P3R –
Helps me keep CO2 levels in check in my tank
Easily shows water CO2 levels with a visual indicator, at first my levels were too low, now they’re a tad too high. The CO2 has dropped my PH down to 6.0, I will readjust my flow rate so that the Ph is little bit higher and the color of the drop checker should turn a tad bit darker. The CO2 drop checker is very simple and easy to help me make sure my plants have the proper amount of CO2 that they need, I actually have only had them in my tank for 3-6 days and already had tons of new growth!
Jay –
Does not change colors
First drop checker came in damaged from shipping. The replacement appears to be in good quality but the solution that goes into the checker does not change colors. It’s been in the aquarium for a few days and the color has not changed.
CoffeeBean –
works
Does what I need it to do, seems to be working. (I did separate water tests that seem to give the same results) so I’d say it’s doing it’s job! looks cute in the tank so it’s not really an eye sore. 10/10
Tim –
Good price for including the indicator.
Jim L. –
Aquarium co2 level
Mark Willmer –
works like it says
Dave Fiorillo –
Works excellent! great value in my aquarium
Danielle Ethier –
Everything was perfect with this purchase and its use. Thanks