Help... what can i put behind my heater?

[Crazy8]

I have a 5 gallon acrylic tank with 1 very curious betta. I'm worried about him trying to get to the suction cups behind my new heater and then getting stuck. I read about people wrapping loofah netting around the suction cups to fill the gap.
As I researched this I found out out the loofah netting deteriorates fast in the tank. What other material could I use OR does anyone have any other ideas of what I could do to close that gap??
As of right now I have a preset tetra 50w heater and would like to replace with a adjustable one. I was planning on taking that one and putting the new in and just let it sit in there for a half and hour before plugging it in, is that right way to do it?
Thank you for any help you may have. I attached a pic.

 

[Crimson_687]

Generally if a fish can fit through something, unless it narrows, they won’t get stuck.

You can use sponge media or filter floss to fill the gap. You can also leave the heater off the suction cups

 

[Crazy8]

Generally if a fish can fit through something, unless it narrows, they won’t get stuck.

You can use sponge media or filter floss to fill the gap. You can also leave the heater off the suction cups

What would be long lasting filter media or filter floss?

 

[Crimson_687]

What would be long lasting filter media or filter floss?

Sponge media and filter floss you should be able to get at any fish store or pet supply store. The sponge is probably a better bet here. If for some reason they don’t have sponge media, buy a foam algae scrubber and use the material from it.