Ph Question

[Haveagojoe]

What determines the ph levels in the tank, i tested the water today and got a reading of 5.5 so I immeidiatly did a 50% water change and took another reading 6.5, in between I tested the tap water and that came out at 7.0 so i presume another change tomorrow will bring it to around 7 which is where it should be i presume.
How does the ph levels change? is it because I am dosing with c02, I use the nutrafin system so its running all the time, will that mean more frequent water changes, at the moment I do 10% once a week is that enough or do you think I should increase it, can the type of wood affect the levels or the type of rock,any help and I would be very grateful.

 

[Haveagojoe]

Bump

 

[Liamm]

For most types of fish I think a pH of roughly between 6.0 and <8.0 is okay for them). You don't treat pH the same as you would with ammonia etc, basically you decide what pH you want and try and stick to it, a fluctuating pH is alot more stressful to a fish than a higher / lower pH than what they're used to in the wild. My tap water reads at about 7.8 and I have some bog wood in my tank which brings it down to roughly 7.4 (as bog wood release tannic acid (I believe this is what makes the water yellowish)), limestone will also affect your pH. Also, dosing CO2 will also affect your pH.

 

[Haveagojoe]

Thanks but 5.5 is not really desirable is it?

 

[StandbySetting]

You're dosing CO2 which when it dissolves into water will create carbonic acid.

The equation is as follows: H20 + CO2 = H2CO3, the acid will then of course decrease the PH of the water, the PH decrease is not due to mineral content so shouldn't in theory cause any issues.

 

[Haveagojoe]

Chemist Im not but thanks for the reply m8