" wrote in message
m...
I'd recommend dolomite, which can be bought at any garden shop.
MgCa(CO3)2
it doesn't add a lot of sulfate or Cl to the system, targets just what
you
need. Unless finely powdered it won't bring up the gH really fast, but
it
will work.

This is good too.

Why is SO4 bad though? Cl is a given to a certain degree but SO4?
I've had very high levels and never saw anything over a number of years.
Regards,
Tom Barr

I'm sure there are some fish that prefer high sulfate water. I was just
assuming most tropical fish do better in reasonably low sulfate water. No
real data, but in the back of my head, I think sulfates tend to be higher in
arid regions.. could be wrong.

High sulfate water is related to all sorts of increased diseases in
humans..(so is super soft water or super hard water). The geographic
correlation between groundwater and disease is an interesting subject. Too
little or too much dissolved solids in water isn't good... over a life time.
Unless you are in parts of NE Wyoming where MgSO4 is common in the water,
then it is rough in the short run. Fortunately, the Gillette has had the
pipe line bringing in Madison Formation water for years. What this has to
do with fish I don't know ;-)

My thought was basically why add something to a tank that you really don't
need and isn't going to be utilized by the plants to any high degree. Also
sulfates are involved in certain types of biodegradation....sulfate reducing
bugs, methane is a common by product.. Not a bad thing when dealing with
gasoline of other hydrocarbon contamination... I don't know what they'd
produce in an aquarium.... I'm a geologist not a bio-chemist.

Bob