Ph And Co2

[rockerBOO]

I currently have a CO2 setup on my tank, and a PH controller. When I first put my PH controller in there, it seems I had PH of about 6.6.

Then, I got a piece of Mopani wood in there, and it seems over the course of a couple of days, my PH is now from 5.0 -> 5.4. All of my fish enjoy it on the "slighty" acidic side, so they are doing good.

I was curious on this wood is causes the PH to change this dramaticly. I am currently not dosing CO2, for fear it might lower it some more.

Also, I was wondering, if this is stable, if it would be ok to add in CO2, and not lower the PH a lot.

Thanks in advance

 

[Bignose]

What are the KH and GH measurements? That will tell you a lot more about the stability.

 

[mav8989]

I don't know much about CO2 and its effect on PH, but I do know that some natural wood decos can lower PH. I used something similar and had the same effect. Basically, my understanding is that the natural tannins in the wood are acidic. (tannic acids) I needed to "steep" my wood in very hot water over and over, like making tea, to lower the effect - b/c in my case the fish in that tank did not prefer the lower PH. Perhaps start brewing around tea time....

I'm sure someone can tell u more about the CO2 aspects....

 

[rockerBOO]

I will take some measurements in the morning.

And the tannins could do it, though they had been in another tank for a while, and the water color had not changed at all, though, could still be the case.

 

[Dave Spencer]

RockerBOO,

Going off a slight tangent, but in my opinion, pH controllers and CO2 injection do not work well together. The key to adding CO2 is to keep it stable up to a maximum of 30ppm, and make sure it is a non limiting nutrient.

With a pH controller constantly knocking off the CO2, you may never reach the desired ppm, and stability may be an issue, resulting in BBA and staghorn algae.

I use a CO2 dropper with 4dKH solution to control my CO2 levels. It is far simpler and cheaper than a pH controller, and gives greater stability.

I have very soft water, that I have measured down to 2dKH before, use wood that leaches tannins, run CO2 at 30ppm and have never had a pH crash. Admittedly, I no longer measure any parameters in my tanks, but I don`t need to. My fish and plants tell me all I need to know.

If you still have your doubts, you could always add a pinch of GH booster at water change time. The plants will appreciate the Mg and Ca it adds.

Dave.