Performing 10% Water Change

Just now I performed 10% water change of my aquarium.

At 10.00 p.m.

The temperature is 27.5 celcius. After half an hour, I test a sample of the aquarium water. The result :

Calcium = 560 ppm
pH = 7.6
dkH = 10

My concern is the pH level. I'm about to raise the pH level to 8.4. But it should be slowly. Sudden raise will kill 'em all. Huahaha...

Maybe I'll try with the Kalkwasser. Tomorrow I'll make a dripper to drip the Kalkwasser into the aquarium. From the forum I read, it should raise the pH. The only problem is that very difficult to get the Kalkwasser powder in this area. I mean Tawau. Luckly I have a friend who got a bottle of it. I should ask him for it tomorrow ;-) Hope this gonna work. Wish me luck.