can i put algae eaters in my outside pond?

If you live in a temperate climate (Like 95% of North America), probably not. Unfortunately there are no really great algae eaters that are appropriate and available for outdoor ponds in this area. There are fish that nibble, to be sure, but none of them are going to solve an algae growth problem. Plecostomus, and Chinese Algae Eaters are the common algae eaters you will find in petshops but they are both intolerant of cold water. I suggest getting a UV sterilizer and shading your pond.

as long as they are fish that can handle the tempreture variation in the water of your pond you should be fine i have bristle nose catfish in my tank and the temp ranges from 8 to 35 degrees celcius

Depends where you live.

They are tropical fish, and if you live any place where it gets even close to a frost the pleco will probably die. But in Florida or South California, yes you could.

Ian

Sure I dont see why not. Make sure that whatever fish he is with is that he is bigger than their mouth size.