Air bubbles in reagent bottle

[JaviVG]

Hi.
On Saturday I intalled KHD.
First test 14dkh. (Normal, the reagent was not in the end of the tube inside KHD)
2º test. 7.4 (10 min later)
3º test. 7.4 (2 hrs later)
Tritation test says 7.5
I increased the carbonate amount a little. (From 8 times a day to 12 times)
24 hrs later I observed air bubbles in the bottle, not in the tubes.
4º test. 7.2
5º test. 7.2 (20 min later)
The system can manage my carbonate feeder to increase or decrease the times it drops carbonate, great product. But, those bubbles are a problem?
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