Tips on electricity safety wanted!

[JohnnyTabasco]

Today my heater died... and it got me a little worried.
Many of the things I got only have two "legs".
How can I make sure I don't get electrocuted when most of my stuff is not grounded?

 

[143MPCo]

@Brew12

 

[Brew12]

The cheapest and easiest way is using a ground probe.

https://www.reef2reef.com/threads/using-ground-probes-in-aquariums.270479/

Adding a GFCI and a ground probe would be ideal. I encourage you to read the link above and the comments to see the pro and con arguments so you can make an informed decision