If it explodes, it will probably leak all kinds of oil into the tank. And whatever money you save, you will spend on electricity costs. THose things are not too efficient.
Don't do it, don't risk your stock it's got an oil filled motor that if it ever leaks will kill your fish.
You need to buy a pond pump or powerhead specifically for ponds or tanks.
Also, the manual says "NOTICE: This unit is not designed for applications involving salt water or brine! Use with salt water or brine will void warranty."
Thx guys ... I got the pump from a friend and was uncerten did not have any info and had a har time finding some . . . I guess I use it to mix my water change water and fill tank / Minimal use .