Thanks Bruce,

Yesterday I disconnected the under tank heating pad. It is designed for that
purpose so I don't thing it should damage the tank. I did it mainly to lower the
water currents going thru substrate. I haven't got a chance yet to go to my LFS
but maybe in a day or to I will go buy some of those plant tabs... By the way
which ones are best?

--
Marvin
hlavac (at) rogers (dot) com


"BruceKGeist" wrote in message
...
My guess is Tom will be able to answer this better than I.

I do not think substrate heating is a bad thing unless you are having problems
keeping your tank at a good temperature. You have your tank at 86 degrees for
discus, right? I can't imagine you are having trouble keeping your tank below
this temp, but if you are, by all means shut off the heat.

There is one thing you should be cautious of. I am not sure how you are
heating the under side of the tank, but if there is enough of a temperature
build up you might crack glass. That could be a big bummer. I suppose you
have already considered this. Glass generally cannot tolerate too much of a
temperature gradient.

I seriously doubt that heating the substrate will cause too much plant tab
fertilizer to seep into the water column. If you want to be sure, you may
want
to monitor your iron, nitrate, potassium, and other critical nutrients to
determine if too much nutrient is seeping in the water column.

As for plants liking warm bottoms, well, they don't often get that in their
natural ecology. Therefore, I of reject that hypothesis. I think someone who
lives in Detroit (like me) in the winter was feeling cold one winter day, and
decided plants must like warm bottoms! The only reason I've heard that makes
any kind of sense regarding advantages of cable heater is as Tom suggested,
circulation of nutrients. If this is unnecessary, as I am beginning to
believe
it is, then why waste the money!

As an aside, I like the Seachem test kits for everything except for Potassium.
(Seachem does not make a Potassium test kit that I know of.) For Potassium
testing I use the Aquarium Pharmaceuticals kit. If your nutrients go out of
balance, then consider testing your setup without heating. You probably
already have all your test kits, but if not, that would be my recommendation.

-Bruce