Heater bare against acrylic?

[HappyFace]

I have a spare Eheim 300 watt heater that doesn't have a cage or suction cups. Can I lay it in my acrylic sump or will it damage the sump? It hasn't been used in 2 years but it has some odd wet look inside is this normal?

[HappyFace]

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[Altum Nut]

From my personal experience I had a 250W Eheim laying on bottom of a 43g acrylic tank for 3 years and found no damage as a result. In addition I have also had Eheim heaters show sweat inside that never posed any issues. I think yours had the same but dried up and rust developed when it was stored.
That was my experience but you will have to make the final call if your comfortable to put it back in service.

...Ralph

[HappyFace]

From my personal experience I had a 250W Eheim laying on bottom of a 43g acrylic tank for 3 years and found no damage as a result. In addition I have also had Eheim heaters show sweat inside that never posed any issues. I think yours had the same but dried up and rust developed when it was stored.
That was my experience but you will have to make the final call if your comfortable to put it back in service.

...Ralph

Thank you Ralph..