Do plants lower the pH?

[Liz]

All,

My water's pH is 7.4 and as stable as the day is long (have a
not-planted tank and the pH never fluctuates - this is the pH out of
the tap).

Recently, I got a 6 gallon tank, and put some plants in with a
boat-load of Flourite for a substrate. After a day or so to let the
tank settle, the pH in this tank was 7.1 or 7.2. I haven't added
anything else to the tank (except a betta) - no store water, no
chemicals other than AquaSafe to treat for chlorine, etc. Could the
plants do this? Or the Flourite (seems like it would do the opposite)?

Anywho, I'm keeping an eye on the pH to make sure it doesn't crash, but
wanted to know if this was a known reaction with plants or if I should
be watching for something else...

Thanks,

Liz

[KStringer]

Are you injecting CO2 at all? This could lower the PH temporarily.
Also, do you know your KH? If it's really low, anything acidic
introduced into the water could lower the PH once it overcomes the
buffer.

[Liz]

No, have not injected CO2. KH is around 170-180. GH is about 100.

Thanks,

Liz

[fish lover]

On 9 Nov 2005 11:17:55 -0800, "Liz" > wrote:
You may want to put in some shells in the tank. That may keep the PH
to 7.5. They will acting as buffer and you don't have to worry about
ph crush. You may have to add some more shells once a year or so
because they just 'melt' away slowly.

I learned my lesson the harrd way. I was trying to lower the PH in my
tank and it kept bouncing back. Finally some people told me about the
shells I kept in the tank. I took them out and the PH came down
without any big effort.


>No, have not injected CO2. KH is around 170-180. GH is about 100.
>
>Thanks,
>
>Liz

[Liz McGuire]

Thanks, fish lover. The tank seems to have stabilized at 7.2 (pH) and
80KH. I'm still doing readings every week, sometimes more often. As
long as it stays stable, I'm not concerned about raising or lowing the
amounts, but if for any reason it becomes unstable, I'll keep your
suggestion about the shells (I've also read this elsewhere, and it
seems to be one of the more stable approaches - compared to adding
chemicals / powders, which I'd prefer to avoid).

Thanks,

Liz


fish lover wrote:
>
> You may want to put in some shells in the tank. That may keep the PH
> to 7.5. They will acting as buffer and you don't have to worry about
> ph crush. You may have to add some more shells once a year or so
> because they just 'melt' away slowly.
>
> I learned my lesson the harrd way. I was trying to lower the PH in my
> tank and it kept bouncing back. Finally some people told me about the
> shells I kept in the tank. I took them out and the PH came down
> without any big effort.
>