A couple questions about substrate heaters

[Gillie]

I was thinking about getting one of these, but I have a couple questions first. How well do they work, and will I need to remove my regular heater? Any advice is greatly appreciated.

 

[Purrbox]

While these were very popular when they first came out, by now most people have decided there is little to no gain for the expense. There are still a few that swear by them, but most have determined that their plants grow just as well without them. I'd recommend saving your money for something else.

If you still want to give them a try, don't get rid of your regular heater.