Black Gravel, Alkaline Water

[Rod Bacon]

My ph seems to be a little higher than I'd like (It's about 8, but I'm
aiming for 7). The first thing they guy at my LFS said was "do you have
black gravel?".

I thought this was a strange question (this is the 1st time I have ever
bought black gravel). He couldn't explain why, but he said that black
gravel often results in high ph.

Has anyone here experienced this? Can someone explain why? (I assume
there's some sort of alkaline substance being released by the gravel,
probably being accelerated by my RUGF).

[Billy]

"Rod Bacon" > wrote in message
oups.com...
> My ph seems to be a little higher than I'd like (It's about 8, but
> I'm
> aiming for 7). The first thing they guy at my LFS said was "do you
> have
> black gravel?".
>
> I thought this was a strange question (this is the 1st time I have
> ever
> bought black gravel). He couldn't explain why, but he said that
> black
> gravel often results in high ph.
>
> Has anyone here experienced this? Can someone explain why? (I
> assume
> there's some sort of alkaline substance being released by the
> gravel,
> probably being accelerated by my RUGF).


Where did you get the gravel? Most commercial gravel is either inert
rock, or epoxy-coated material rendered inert by the epoxy. The color
of the gravel would, IMO, be irrelevant unless the gravel was black
due the *type* of gravel. Black onyx sand by Seachem, for example,
may push the ph up. I would be looking more at my water supply. Draw
a gallon of your source water, let it sit overnight, them measure the
ph. If it's 8 already, then you're better off either buying fish with
a higher tolerance for higher ph. Most neutral ph fish can adapt to a
ph of 8, BTW.

billy

[Rod Bacon]

I'm going to do a partial change tonight, so I'll measure the tap ph
then. I have tested it in the past, and it's damned close to 7.0

The gravel cam from my LFS (not the store that made the ph/gravel
claims). It's not epoxy-coated, rather it's a natural dark brown/black
stone with a max diameter of 6mm (though most are around 4mm).

My main reason for wanting to lower my ph is the recent rapid growth of
hair algae. From reading this forum it appears as though a lower ph may
help to slow the algae's growth.

[Logic316]

Rod Bacon wrote:
> I'm going to do a partial change tonight, so I'll measure the tap ph
> then. I have tested it in the past, and it's damned close to 7.0
>
> The gravel cam from my LFS (not the store that made the ph/gravel
> claims). It's not epoxy-coated, rather it's a natural dark brown/black
> stone with a max diameter of 6mm (though most are around 4mm).
>
> My main reason for wanting to lower my ph is the recent rapid growth of
> hair algae. From reading this forum it appears as though a lower ph may
> help to slow the algae's growth.


I would take a small sample of the gravel and place it in a container of
vinegar. If the gravel is indeed alkaline, it should produce a visible
reaction with the acid. Haven't tried it myself, but I read somewhere
that this is a good way to test decorative rocks to see if they'll
impact the PH of an aquarium.

- Logic316



"The best minds are not in government. If any were, businesses would
hire them away."
-- Ronald Reagan

[Rod Bacon]

This is a great idea.

I have a container of HCL at home, I might use that instead (for a more
aggressive and more visible reaction).

[Robert Flory]

Only if the black gravel was limestone or dolomite,. Lots of it is
Bob

"Rod Bacon" > wrote in message
oups.com...
> My ph seems to be a little higher than I'd like (It's about 8, but I'm
> aiming for 7). The first thing they guy at my LFS said was "do you have
> black gravel?".
>
> I thought this was a strange question (this is the 1st time I have ever
> bought black gravel). He couldn't explain why, but he said that black
> gravel often results in high ph.
>
> Has anyone here experienced this? Can someone explain why? (I assume
> there's some sort of alkaline substance being released by the gravel,
> probably being accelerated by my RUGF).
>