"Graham Broadbridge" wrote in message . au...
" wrote in message
m...

Good idea but why not just add more CO2 and lower the pH, not add more
KH?
The pH is not going to change things by being another 0.2pH units
down.
Having to alter KH is a PITA if you don't have to.

That's a good idea, but the water out of the tap here in Sydney has 0kH to
start with. Every water change I have to add sodium Bicarb to keep an even
6-8 dkH. One teaspoon or two makes no difference :-) Baking soda is
cheap :-)

It would not hurt to add some PO4 at that point also.
2ppm of NO3 is too low BTW and so is 0 ppm PO4.

I'm aiming for the phosphate limitation scenario that is quite popular based
on the infamous paper which I'm sure you've read.

Which has long been surpassed, specially for CO2 tanks. Phosphate
limitation is good for non CO2 tanks, doesn't work too well with
higher light and CO2 as phosphate IS a required element and at such
fast rates of growth, a 0ppm level will likely cause problems. Try it,
you will see for yourself.

Hope that helps
Giancarlo Podio
www.gpodio.com