Getting a New Betta

I will, should the heater be hidden with a plant or anything?
Hiding heaters is a personal choice. If you do, leave some clearance between any plants or decor and the heater — and never let the heater touch or dig into the substrate. Positioning it so any indicator light/display can be seen (from some angle) helps, as it makes it easier to know when the unit is actually heating.

Check the instructions for any heater. Most can be positioned vertically or horizontally, but some only vertically. Suction cups may need to be positioned away from the heating element part.
 
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