Limnophile wrote:
"Altum" wrote in message

Undergravel heating isn't as popular as it was 10 years ago. People who
have tried it say it doesn't make much difference. I would spend money on
a good laterite substrate instead.

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People have a variety of opinions on undergravel heating cables. I've seen a
few planted tanks with the undergravel heating cables, and the plants were
very lush and beautiful. On the other hand, they may have done just as well
without the cables. The theory is that heating the bottom of the tank causes
more water flow through the plant roots, increasing the amount of nutrients
available. Does anyone here have results from any experiments to support
whether it improves growth or not ?

Horst and Kipper did the experiments and found improvement. They talk
about it in the Optimum Aquarium. Tom Barr (a well-trained plant
physiologist) has done carefully controlled experiments and says he
found no differences. George booth found differences but only after a
few years. Plant growth slowed some in his non-heated tanks. Diana
Walstad addresses them in her book but I'm waiting my turn to borrow a
copy to read. Have you seen anything from Amano on cables? I know his
ADA line doesn't manufacture them.

The cables certainly won't harm a tank.

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