Pump silencing question

[Vagabond]

I have an in sump skimmer, Euroreef ES5-3 running on a dolphin DP560 pump.

I love the skimmer but the vibratory noise from the pump is a liitle loud.

Anybody have some reef safe solotions for padding between the pump and the glass bottom of my sump to reduce noice/vibration.

I was thinking a piece of neoprene but did not know if this would degrade over time and be toxic.

Ideas/suggestions/experience appreciated

TIA