Co2 Pressurised Injection In Low Ph Water

[Bobtastic]

Hi all,

As I get more interesting in planted aquariums the more I lean towards having to get pressurised CO2, but I understand the addition of CO2 lowers the pH of the aquarium. That would be ok if the starting pH (of the water out of the tap) was 7+, but what happens when it is already as low as pH6?

Will adding CO2 drag the pH down further? Does that mean that I wont be able to use pressurised CO2?

Thoughts pls...

 

[baron von bubba]

Hi all,

As I get more interesting in planted aquariums the more I lean towards having to get pressurised CO2, but I understand the addition of CO2 lowers the pH of the aquarium. That would be ok if the starting pH (of the water out of the tap) was 7+, but what happens when it is already as low as pH6?

Will adding CO2 drag the pH down further? Does that mean that I wont be able to use pressurised CO2?

Thoughts pls...

adding co2 will lower your ph, the average ph drop is from 1 to 1.3 if you plan to hit around 30ppm

is the tap water 6ph straight from the tap? leave it out in a glass for at least 24 hours and test it, that way any any co2 present in the tap water will have gone and you will have the actual ph of the water.

 

[Bobtastic]

Yeah, it's pH6 out of the tap. Done the leave it out for an bit and test it again and it was still at pH6. I have added some crushed coral in to one of the filter trays to stablise/increase the GH/KH. Not tested it for a little while as I don't really have anything in it but on the other tank it didn't really have much of an effect.

 

[RadaR]

The only problem with your pH going down to 5 would be to the nitrifying bacteria as I'm sure they aren't efficient or don't multiply at this pH.
Fish and plants would be ok though.

 

[Bobtastic]

So basically if I can't raise the pH or at least increase the GH/KH do a point that the pH is a solid as a rock I can't use pressurised injection of CO2?

 

[baron von bubba]

So basically if I can't raise the pH or at least increase the GH/KH do a point that the pH is a solid as a rock I can't use pressurised injection of CO2?

you will never get the ph "solid as a rock" and there is no reason to try and achieve this! (raising gh/kh certainly wont do this)


what is the kh of the water?

baking soda will raise the kh and ph.
i think having a water butt to premix the water before a water change would be the way to do it.

i found some figures but have no idea if they are correct.
added to 100l of water 4 teaspoons would raise the kh 10 and the ph by 1


another option would be to use excell or some other liquid co2 supplement, but on a big tank that'd cost a fortune! :0/