PH and Co2 Question

[buzzy]

hi i have just setup a Co2 injection setup.i have a question about the PH, while the Co2 is running will my PH just keep dropping or should it get to a certin level and stay there? say from 7 - 6.6 then level out??any help would be great

[Proteus]

Unless you have a good KH level, it will keep dropping and eventually crash.

C02 is an acid, and without any carbonate hardness in the water there is nothing to buffer/stabilise the effects of C02.

Are you using a pH controller at all?

How are you controlling your C02 flow to the tank, via a timer?

[axl]

Hi,
you need to find a stable ph by how much co2 you are putting in your tank. I have just setup a co2 system about a 1 month ago and it took me 2 weeks to get the ph stable. Im not using a ph controller and i reckon you dont need 1 you just need a digital ph meter and you check it 2 times a day, 1 in the morning before lights come on and this will give your lowest reading for the day and tghen it will go up when the lights come on. Im running my ph at 6.3 and kh at 2.8 which equels 30ppm of co2 and 3 bubble per second. Make adjustments to get your co2 at 30ppm. Read up on the net as much you can on co2 tanks and if you have any other questions just ask. Your ph will stay the same once you have sorted out your bubbles per second and i dont use carbon hardness buffer either and my kh is fairly low. Sorry for the long post
cheers axl

[Davo]

Axl,

I think you need to raise your PH because if you use a CO2 calculator or chart ie "Chuck's Planted Aquarium calculator", and with your PH of 6.3 and your KH of 2.8 your CO2 woud be 42 ppm which is pretty high.

As you said you need your CO2 around 30 ppm. With a KH of 2.8 you need a PH of around 6.4 to 6.5.

Dave.

[axl]

Hey Davo,
yeah sorry about the miss print but my kh is 40ppm which is 2.2 and the ph is 6.3 which equels 33ppm of co2 thatnks anyway
cheers axl

[goldfish]

hey guys,,,,where can i find this chart??

[Davo]

Have a look at www.csd.net/~cgadd/aqua/index.htm

Dave.