Degrading CO2 indicator

Hi,


I am brand new to the high tech planted tank scene, but have hit a snag..



Has anyone had issues with their CO2 indicator crashing out in their checker? It was OK for about 3 weeks then crashed out and turns completely transparent.. Not pale yellow.


I have replaced the indicator in the bulb (was green after the first hour or so) and the same thing happened again overnight.

Any ideas on why this would happen?



The tank is about 4 weeks old, through its cycle period, and the indicator / checker was bought at the time of tank purchase..

Please help.



Thanks!



I didn't find the right solution from the Internet.



References:

www.aquaticplantcentral.com/forumapc/general-aquarium-plants-discussions/138290-degrading-co2-indicator.html

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