Substrate heating

[bullyboy]

I found this article and it got me thinking, are they useful?
Anyine have any experience with them?
Thanks

Substrate Heating Coils in the Planted Aquarium

 

[Fresh2o]

I actually tried this in the 90s. Idea came from the same book mentioned in the article. Instead of heating cables ($$$) I created false bottom using eggcrate and plexiglass. A submersible heater was beneath the plexiglass.
I'm not sure how effective it was. In theory it is supposed the help circulate nutrients in the substrate. A short circuit in the heater's electrical cord forced me to use conventional heating.
You hardly hear about substrate heating these days.

 

[bullyboy]

I was thinking about making a substrate airation system and just running the heat cables through that.
This way i could always take it out if it went airy with out having to pull up plants.
I think it could be useful in a taller tank.
I wonder if i could use the parts from an under gravel filter maybe too?