More lights = Higher PH levels

["Greger Lindstrand" <greglind at algonet_se>]

Yesterday I doubled from 4 to 8 tubes of 36 W on my tank and the PH level went from 6.84 to 7.19!

But first, A special Thanks goes to Scott Hieber who so kindly helped me with getting the wiering correct. Thank you Scott! Your help was greatly appreciated.

Well, I have not changed anything at all among the parameters of the tank. Done nutting but adding more lights and removed the cover glas from the tank top.
The PH went up! I wasn't expecting this and I am currently trying to figure out what could be the cause of this.

I have 2 hypothesis:
1. Removing the cover glas has given free access to gas exchange over the complete surface area. Wheras before, the cover glas trapped some CO2, thus hindering exchange.
2. The increased bubbeling has increased the surface agitation and thereby excited the gasexchange rate.

Is an increase of the PH level, an expected reaction, when one adds more lighting?
Anyone else who had a similar experience?

Best regards
Greger Lindstrand