CO2 carbonation system for the aquarium according to Jarden Sk - without Drop Checker.

Jarden Sk

New Member
Oct 31, 2022
I have been using this system for over a year. It can also be applied with the EI and other fertilization methods. I use inorganic acids H2SO4, H3PO4, HCL. It works on the principle of direct consumption, without excess CO2 in the system.
HCL is the most available and safety precautions must be observed when handling. It is diluted with distilled water. Always pour acid into water, not the other way around! Keep chemicals out of the reach of children in a labeled bottle with a safety cap!

1. A system for hard water where the values are around Gh20 and Kh 15. This method requires the use of a more concentrated acid. The harder the water, the more concentrated acid is needed to adjust the PH. In the aquarium, I prefer Ph 6.8 and therefore I use H2SO4 37% or HCL 31% acid for hard water. Change the water in the aquarium and use the Ph controller to determine the Ph of the water in the aquarium. Then you gradually add drops of concentrated acid to the filter outlet, after a few minutes the water will be mixed to the required Ph in the aquarium. This action is done just before turning on the CO2. I turn on the CO2 about half an hour before the lights. When you manage to adjust the Ph with acid, we saturate the CO2 from the bottle so that the Ph remains at the selected value only while the lights are on. That way you will be set with the consumption in the aquarium. In the morning or before starting the carbonation, you again adjust the addition of acid drop by drop to the desired Ph. This is repeated every day until the water is changed. By adjusting Ph with acid, you also adjust Kh.
2. The system for soft water is similar, but the difference is in the concentration of added acid. Soft water is a fragile system of carbonates and bicarbonates, and therefore you only use a weak inorganic acid or none at all to adjust the Ph, because a concentrated one will also dissolve HCO3, and these are usually very low in soft water. The procedure is the same as for hard water, but the acid must be weak - you must dilute it so that it does not dissolve your bicarbonates.
3. System for water from RO and remineralized water in the aquarium. Here it is similar to above and it depends on what Gh and Kh parameters you create and what you prefer in the aquarium, you will also choose the concentration of inorganic acid accordingly. Adding CO2 then depends only on maintaining the Ph in the aquarium during the lighting.

If your Ph stays at the selected value during lighting, also check the Kh, it may rise a little, then you need to reduce the CO2 a little more. Thus, the Ph and Kh values should be stable during lighting.
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