Do you have the same plants in all of the tanks? Maybe you added a plant
that loves nitrates? Is the fish load similar between these tanks? What
about lighting?

Ron

"jduprie" wrote in message
news:z3Qpa.602410$L1.171543@sccrnsc02...
I've got somethign I've never seen before. I havea "new" (about 2 months
old) 125 lightly planted tank, witha variety of fish in it. After the
initial cycling, the chemistry had setteld down to a pretty "normal"
ballance, and was staying nice and constant (light presence of nitrates,
no
ammonia, teeny bit of nitrite).
Then, overnight, *everything* went to zero - none of the test kits show
the
presence of any nitrate, ammonia, or nitrite. I've never had to add any
suplements to any of my other tanks, (similar set ups), and I've always
(and
still do, so the test kits are OK) had traces showing up......

any ideas?

thansk
--JD