水草情迷

Is there anybody using heating cable in your tank ?
Could you share you precision experience for us ?

There are several setting I am not sure, such as
the setting temp. for the tank ? for the bottom ?
How long does it work in each day? whole day ? or just the few hours?
Connecting with a temp. setting device( regulator/ temp. controller)? or just plug in to the main?

Any information in how many watt per Liter?

I am using heat coil, and am very happy with it. First, it totally fix the rotting roots problem, and secondly, it obviously achive the claim of transport nutrients around the substrate. I observed that no individual plants get more nutrients than others after I fertilized with plant sticks, which means nutrients is really being transport around the substrate.

I have it on 3 hours every 12 hours, by using a timer. But I also have a chiller, so you might have to consider one to achieve heat coil's maximum effect.

BTW, I have this substrate for a year now, still no sign of needing a new substrate. I would put this on benefit of heat coil, but really not easy to be sure.

Watt per litre isn't important, just get enough coil to cover up your tank base.

I am using a 25W bottom heating core for my 36" tank filled with ADA Amazonia Soil. I didn't use any temperature control (they are expensive) also 25W cannot do much temp. changes to my tank. The main purpose of the bottom heating coil is not to raise the water temp, but improve the circulation inside the substrate as Macbrush mentioned. I turn it on from 11:00pm to 11:00am for 12 hrs. I don't have any water cooler.

But honestly speaking, I didn't see much different after I use the heating coil. It may because my other water parameter is not optimal. I feel that it won't help much if your tank is not running very well, but if you tank is running at 95% optimal, it can help the rest 4 to 5%.

I think if your tank have other areas to improve, e.g. water cooler (keep temperature at about 25), HQI lighting, good filtration system, enough fertilizer they will be more effective to optimze your tank. If you already have them in place, substrate heater seems to your choices

For more detail information about the rationale of it you can see
http://www.dupla.com/e005.htm
http://faq.thekrib.com/plant-cables.html