I believe most would suggest you first check to make sure you dont have
anything which will naturally raise your pH such as limestone rock, concrete
blocks (that's the only two I can remember). If not, a stable pH even
though on the high side will be fine for your fish. It is the significant
pH swings which are bad for the fish. I would think your swing is very
common. Sorry I was going to say no problem but there are also some plants
which wont thrive as well (??) and ammonia (if it developes) is much more
toxic at higher pH. HTH some Bill Brister - Austin, Texas

Right. ) Gonna have to change your Newbie handle.

I would add: Check your KH/Total Alkalinity, do a test on your tap water of
both pH and KH. With no showing of ammonia, a water change is always wise
and you should be doing 10-15% weekly anyway. See this website as a good
reference: http://www.koiclubsandiego.org/H2oQual.html ~ jan


See my ponds and filter design:
http://users.owt.com/jjspond/

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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