CO2 Visual Test is a permanent test, allowing to observe the CO2 level in aquariums. CO2 (carbon dioxide) is one of the most important elements for aquatic plants.
Plant growth stagnates with insufficient carbon dioxide levels, on the other hand to much of CO2 is harmful for fish.
2 color cards (stickers) may be used depending to the dKH .
The card n°1 will be used with a dKH of 2° up to 7°.
The card n°2 will be used in case of a dKH between 8° and 15°.
The test liquid should be changed after every water change or every 14 days, in order to assure accurate color indication.
O-rings should be greased with silicone grease from time to time