SunGrow Glass Drop Checker with Solution for Betta Fish Tank Plants, Aquarium CO2 Indicator Kit

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About This Item

Details

  • High-quality carbon dioxide level testing kit for your aquarium water.
  • Color change shows the results.
  • Provides accurate CO2 readings all day long.
  • Glass drop checker keeps the CO2 levels in your tank consistent.
  • Easy to use and visible in even the busiest tank.

Frequently bought together

Questions & Answers

2 Customer Questions

Does this come with the fluid or is it just the glass drop checker?

Answer by Chewy • May 04, 2023
This kit comes with the solution.

can you buy replacement liquid or do you have to buy a whole new kit?

Answer by Chewy • Feb 07, 2026
CO2 Indicator Solution can be purchased separately as the SunGrow Glass Drop Checker with Solution for Betta Fish Tank Plants, Aquarium CO2 Indicator Kit is compatible with all brands.
Reviews
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4.2
Rated 4.2 out of 5 stars
10 Ratings
Terms & Conditions

6 Customer Reviews

Rated 4 out of 5 stars
By Christopher on Oct 6, 2025

Seems easy to use

Seems easy to use. I say "seems" because there really are no instructions. Just a solution bottle with unclear English directions. The bottle says "15 drops change

Seems easy to use. I say "seems" because there really are no instructions. Just a solution bottle with unclear English directions. The bottle says "15 drops change monthly". The product photos on here say 3 drops of solution. There are no directions for placement in the tank or an estimate of how long it takes to get a reading or what the color means. Luckily some of the other reviews provide some insight. Overall, it does seem like good quality and should be easy to use.

Rated 2 out of 5 stars
By Mylo on Nov 9, 2025

would work great if it stayed

suction cup always unsticks within 72 hours

suction cup always unsticks within 72 hours

Rated 5 out of 5 stars
By Jaxx on Apr 16, 2024

Works great!

I have one for my betta tank and my plant tank! The work great for monitoring the co2 level, this saved my dwarf hairgrass! In both tanks so I know that there getting

I have one for my betta tank and my plant tank! The work great for monitoring the co2 level, this saved my dwarf hairgrass! In both tanks so I know that there getting enough

Rated 5 out of 5 stars
By Brian on Jul 18, 2024

SunGrow Glass Drop Checker

Works as it should. I will buy again.

Works as it should. I will buy again.

Rated 5 out of 5 stars
By Rotala on Oct 17, 2023

User friendly CO2 monitor

I got this to use with a CO2 cartridge system, and it works really well. It's a good deal since it comes with the fluid you need. It's easy to use, but remember

I got this to use with a CO2 cartridge system, and it works really well. It's a good deal since it comes with the fluid you need. It's easy to use, but remember that the fluid takes a bit of time to change color, so go slow when adjusting your CO2 until you know the right levels for your tank

Rated 5 out of 5 stars
By SeaShells on Oct 2, 2023

Must have for planted tank

Having this for my tank has made life easier. Now, I don't have to wonder whether my tank has too much or too little CO2. It's green when the CO2 levels are right,

Having this for my tank has made life easier. Now, I don't have to wonder whether my tank has too much or too little CO2. It's green when the CO2 levels are right, blue when it needs a bit more, and turns yellow if there's too much. It's been a great addition to my setup