rising pH issues

[credenza]

55g planted tank.
Fish: 8 espei rasboras and 6 zebra danios
Setup for 2 mths (including 1 mth fishless cycling)
Water changes 25% per week

I noticed today, just before my water change that my pH was just over 8.0. Until now my pH was always around 7.6 (based on my water test kit with the color chart)

What could be reason for the pH rise?

What are the downsides of high pH?

Will more frequent water changes help with keeping close to normal levels?

PS : I had inadvertantly posted this message in the General FW forum and was unable to delete it.

[aquariumfishguy]

Am I seeing double? :p

Look for my post in your other thread...;)

[credenza]

Thanks aquariumfishguy!

That's right. U were seeing double because somehow my message was posted in the other forum and I was unable to move/delete it.

U r right. I was thinking the same too that the pH would probably go down as the water gets dirtier. But I am not sure why it climbed. Are there any possible reasons? I do add plant fertilizers in small amounts with every water change.

Also wont the fish be bothered due to the water getting harder?