DIY ATO, mechanical relay or SSR? wich is better?

[CoralPlast]

I guys, eich relay you tink is better for a homemade ATO? I've heard when mechanical get stuck they usually do it in the OFF position while SSR usually do it in ON position. is it true? If that's the case i would probably go with mechanichal since i would feel more safe. What's your tought?

 

[Nano_Man]

On nano tanks I use diy juice bottle gravity fed but if it’s a large tank mechanical will be better the bottle keeps salinity bag on on my nano tanks