"Nick L-S" wrote in message
...



My question is, does pH matter? The water here has a naturally high pH,
but if i try and use pH-down (for the fishes) it just goes back up again
in a matter of days. I dont quite know why, but are there any plants
which dislike a high pH?


Yes, PH matters to plants. Some plants tolerate a wide range of PH, others
are very particular. Research individual varieties to determine thier
preference.
As far as your ph not being stable, you need to increase your tank's
buffering capacity. I have rarely had trouble with this, as my tap water is
close to neutral here. Others will be more helpful in helping you lock down
the ph.