# CO2, hardness and pH



## PDSimon (22 Aug 2010)

Hi, 

I am planning on adding co2 to my tank so am very much a newbie on this subject. I would therefore much appreciate some help understanding how the pH will affected when I dose CO2.

My pH is 6.0 (according to an API test kit) even though my tap water is 7.5. I think this is due to bogwood in the tank. If I dose co2 I believe it would bring it down 1.0 to 5.0pH? 

I have stocked, bolivian rams, apistogramma cacatuoides, diamond tetra, rummy nose tetra and kuhli loach. Now I think all those fish can handle the pH but i'm not sure about the kuhli loach. Widipedia for example says 5.5- 7 so 5 should be ok? I have amano shrimp too, no idea if they could adapt to that pH? most sites say 6.5ish

I also have fairly soft water. An API test kit shown that my tap water is at 3KH and 6GH. Will my tank water be the same hardness or will the bogwood have lowered that too? I can get it tested as well if need be. So I was wondering will I have to dose bicarbonate soda or something to stop any pH crashes.

Thanks for any help, 

Si


----------



## ceg4048 (23 Aug 2010)

Hi,
     The best advice I can give you is to completely forget about all of this. Adding CO2 lowers the pH of the water in the tank but fish don't really care about pH. The pH numbers that you see just happen to be the pH of the particular stream that the fish were captured in. It does not mean that they have problems with lower or higher pH. In fact, many South American fish will only spawn when the pH drops to low levels.

Your KH and GH are fine. There is absolutely no reason at all to make any adjustments at this time. Not having to worry about these makes life much easier. Worry more about CO2 injection techniques, flow/distribution, maintenance, cleanliness and nutrient application. These are the areas upon which to expend the majority of your energy.

If you are new to CO2 then you really need to check the Tutorials section of the forum and study the thread =>CO2 MEASUREMENT USING A DROP CHECKER

Cheers,


----------



## Dave Spencer (23 Aug 2010)

PDSimon said:
			
		

> So I was wondering will I have to dose bicarbonate soda or something to stop any pH crashes.



That is a very TFF sounding question.   Congratulations on finding a forum that knows how to run planted tanks properly.  You will find this to be a BiCarb free, pH crash free, non ammonia adding place. Although it may seem a more complicated place to be compared to TFF, we won`t have you buying test kits and pointless additives in search of some water parameter related Nirvana.

What is a pH crash, by the way? I have softer water than you, tanks full of wood and high CO2 levels and have no pH problems that my fish make me aware of.


----------



## CeeJay (23 Aug 2010)

Hi Si

Might be worth reading this too. 
Will c02 kill fish due to ph changes? 
Some highly respected folk contributed to this thread


----------



## PDSimon (23 Aug 2010)

ceg4048 said:
			
		

> Hi,
> The best advise I can give you is to completely forget about all of this. Adding CO2 lowers the pH of the water in the tank but fish don't really care about pH. The pH numbers that you see just happen to be the pH of the particular stream that the fish were captured in. It does not mean that they have problems with lower or higher pH. In fact, many South American fish will only spawn when the pH drops to low levels.
> 
> Your KH and GH are fine. There is absolutely no reason at all to make any adjustments at this time. Not having to worry about these makes life much easier. Worry more about CO2 injection techniques, flow/distribution, maintenance, cleanliness and nutrient application. These are the areas upon which to expend the majority of your energy.
> ...



Hi, cheers for the reply.

I was thinking this might be the case so thanks for clearing things up. I have looked through all the tutorials and they have been very helpful. The only thing was that I read a few different tutorials and they said different things about what your hardness should be so I wanted to confirm  

edit: Would this mean it doesn't matter whether I use a solenoid or not?


----------



## PDSimon (23 Aug 2010)

Dave Spencer said:
			
		

> PDSimon said:
> 
> 
> 
> ...



 It was actually your forum that made me curious! I think there are two main co2 tutorials and one was below my KH and one was above. I assumed that if you have really soft water that adding co2 could make it drop(badly)? Even the tutorials mention the bicarb 

I'm glad to hear other cases of water like mine... I thought it'd be ok though. Cheers for the reply.



			
				CeeJay said:
			
		

> Hi Si
> 
> Might be worth reading this too.
> Will c02 kill fish due to ph changes?
> Some highly respected folk contributed to this thread



Thanks Ceejay, some good info in there cheers.


----------



## ceg4048 (23 Aug 2010)

PDSimon said:
			
		

> Would this mean it doesn't matter whether I use a solenoid or not?


Correct. The solenoid is optional. You have a different set of problems with CO2 24/7 as opposed to timed application. Try one way and see if it works for you.

Cheers,


----------



## Dave Spencer (23 Aug 2010)

PDSimon said:
			
		

> It was actually your forum that made me curious! I think there are two main co2 tutorials and one was below my KH and one was above. I assumed that if you have really soft water that adding co2 could make it drop(badly)? Even the tutorials mention the bicarb



I am confident that you needn`t worry about adding BiCarb.

Here is Tom Barr`s take on it.



			
				plantbrain said:
			
		

> Basically, CO2 is not a salt, KH is.
> Rapid changes in pH due to KH= bad.
> Rapid changes in pH due to CO2= does not matter.



It is adjusting the pH via the KH that will bring your fish grief. I dare say the pH of my tanks swings at least by a value of 1 during a twenty four hour period, but with no problems. Obviously there are fish that will not like yours or my soft water, but that is another story.

Dave.


----------



## PDSimon (23 Aug 2010)

Thanks guys, really appreciate the help. 

Will probably start a journal soon!


----------



## PDSimon (23 Aug 2010)

Ok I think I have what I want, could someone please double check to see whether I've got everything! 

- Reusable co2 canister, either aqua medic or sera
- regulator, is this definately sufficient for reusable co2 bottles? (and safe!) http://cgi.ebay.co.uk/CO2-Doppelman...339728503?pt=de_haus_garten_tierbedarf_fische sorry its in german but the translated link just wouldn't work   
- bubble counter http://cgi.ebay.co.uk/GX-CO2-Bubble...ser-Ada-T-/250305632412?pt=LH_DefaultDomain_0
- reactor - http://www.thegreenmachineonline.co...2-system/co2-diffusers/aqua-medic-reactor-100
- drop checker http://cgi.ebay.co.uk/Drop-Checker-...-Solution-/250632188737?pt=LH_DefaultDomain_0
 - Sera tubing

anything else I need? Is this all ok stuff, or would it be worthwhile changing things around? any help will be much much much appreicated!!!


----------



## CeeJay (27 Aug 2010)

Hi

Looks like you've got all the bits you'll need to get you going.
You never mentioned the size of your tank. Bigger tanks obviously use more than little tanks, so you may want to consider the FE as your source of Carbon. Your chosen regulator looks like it has the correct fitting for connecting straight on.
Also, FE's work out a lot cheaper in the long run.
Check out this useful thread 
Fire extinguisher CO2


----------



## PDSimon (28 Aug 2010)

Hi Chris, thanks for the confirmation. I think i'm going to get a 5kg cylinder and my tank is about 30USG so it should last a fair time!


----------

