Size of pump

[Finally retired]

I have an 8 foot rowboat that i have made into a pond. Can anyone advise me what size pump i need. I would like to make a waterfall with the water spilling over the bow. I tried putting fish in with a small circulating pump but sadly they all Died.
Trying to add a photo of said boat but guess im not tech savvy enough.

 

[combatwombat]

Any small pump doing 1000 GPH or so should work. I doubt the problem with the fish was just lack of pump, though. You need biological filtration.

 

[TheFishGuy]

Mr. Wombat gave you some good advice. Something in the 1000〰 gph area will work well. If you are looking to keep fish I would advise adding some plants and biological filtration additionally.