I had a titanium heater put out by wok called pro time. Please DO NOT GET THIS HEATER! I only had this heater for about 5 months and one night last month the heater malfuntioned and heated my discus tank to 110 degrees. Needless to say all the inhabitants except the pleco did not make it. The pleco is still fine and I do not understand how he is still O.K. I'm really surprised he does not seem to have tissue damage from the extreme heat. The heater was so hot that I could not touch it for at least an hour after unplugging it and ther were burn marks down the side of it. Now, I suppose this could happen to any heater but it is my understanding that there are problems with this heater. However, the company has not recalled it. Now, I am in the process of restocking this tank. Needless to say I am keeping a close watch on the temps. on all of my tanks. About the live plants-there should be no negative effects from the plants. It does not make the cycle longer and in some cases can help the cycle along. From my experience with live plants in my aquariums; it has always been a true benefit. The fish get more oxygen from the plants, the tank has little or no algae, and a tank filled with live plants looks totally natural and so cool. I hope this helps.
Be happy!
Marinemom