Clip – CO2 tester

Not sure if you have enough CO2 in your aquarium? This is important to know if you want to have healthy aquarium plants. The “Edge” drop checker can help you with this.

  • Easily & quickly determine the CO2 level
  • Ideal for open tanks & nano tanks
  • Fast cleaning
  • Free advice via the blog, ebooks & mail

The Edge drop checker is a must-have for a healthy plant tank and gives you more control over your CO2 and thus the health of your plants.


In stock

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Made of strong glass

Gemakkelijke setup

Easy to measure CO2

Open aquaria

Ideal for small open-top aquariums

Wat is this product?

The most important nutritional element for your aquarium plants? That’s probably CO2. Without sufficient CO2, you’ll get all kinds of deformities in the leaves, the plants will lose their beautiful color and worse … algae will develop.

So how do you know if you are adding enough CO2 for healthy plants? Well the “Clip” drop checker helps you with that. Just look at the color of the drop checker.

Easily measure your CO2

Suffering from string algae or beard algae? Or your plants are not growing well (yet)? Chances are that your CO2 is not so good. So how can you determine approximately how much CO2 you have?

Well, first you add drop checker indicator mix. Then turn over the drop checker and hang it on the edge of your aquarium. After a few hours, you will see that the liquid in your Clip drop checker starts to change:

  • Blue? Too little CO2
  • Green? Looks good
  • Yellow? Oy, probably a little too much CO2

Really nice and simple.

Ideal for open aquariums & nanos

The best part about this drop checker is that you hang it over the edge of your aquarium. This leaves you with even less equipment in your aquarium so you put even more focus on your aquascape. This makes it very suitable for nano aquariums, where space is at a premium anyway.

In addition, it is made of sturdy laboratory glass, so it is less likely to break and stays nice and clear.

Free advice & coaching

By the way, did you know that as a customer you are always entitled to free advice & coaching tailored to your aquarium? You get access to the blog packed with useful articles and can download free e-books.


What's the best place for the Clip CO2 drop checker in my aquarium?

1. Turn the Clip over so that the opening faces upward
2. Add drop checker indicator mix
3. Turn the Clip over & hang it on the edge of your tank with the open side in the aquarium

Do I have enough CO2 in my aquarium?

Take a look at the color of the indicator mix:

  • Is it blue? Too little CO2. Carefully add more CO2
  • Green: OK, but you may feel free to add a little more
  • Lime green: OK
  • Yellow: watch out, you may have too much CO2 and that is dangerous for your fish

How should I clean the Clip?

I recommend you do it regularly, preferably with every water change. How to do it? Just rinse with RO water, clean with some filter wool and refill with indicator mix as described above. And ready!

What's the maximum glass thickness?

This drop checker can be used on glass up to 12mm in thickness.


Customer Reviews

Based on 6 reviews
Thomas Overdijk
Clip Co2 tester

Mooie goed af te lezen Co2 tester.

Boudewijn van Kempen
Mooi design, klein juweeltje

De levering was super snel, goed verpakt, duidelijk kwaliteit, intressant reclame materiaal, geen poespas.
Echt een aanrader voor deze hobby.

Roger Janssens
Goede koop

Geeft juist aan bij voldoend co2

eduard a.
heel goed en handig

heel goed en handig een oogopslag zie de co2 toestand in je bak.goede indicatie hulpstuk.

stephan s.
top produkt en makkelijk in

top produkt en makkelijk in gebruik, alleen het vullen was even wat lastig, al met al ben ik zeer tevreden