Bookie, might the sucker catfish you are refering to be the pleco? If so, I do not think these are the chinese algae eaters that Cynthia is refering to since plecos originate in South America. (I could be wrong).
I don't know much about keeping algae eaters with axolotls, but a lot of people will tell you that its probably not a very good idea. Tho many people seem to have been able to keep plecos and axies together with no problems.
I guess it all really boils down to whether you think the benefits outweigh the possible risks. I've been told that the ridges on plecos will injure an axolotls mouth when your pet will attempt to eat it. And I haven't heard much concerning plecos, but like Cynthia pointed out, some species may find your axie appealing and leave lesions on your pet.
I too am considering putting an algae eater with my axolotl. However, with all the negative things I've heard about sticking axolotls and suckermouth catfish together, I'm having second thoughts.
Like I said, I don't know a whole lot about it. How big is your tank? Perhaps a somewhat large tank will allow more space for your sucker fish to hide from your axolotl? Hehehe wait and see what other people have to say