Things that will increase oxygen, surface agitation(moving the water, and it will add more than any air stone or other bubble making device), cooler temps, clean water. Butterfly suckers originally came from somewhat cool, fast moving streams. I believe there are some strains that have been bred to tolerate warmer water, and I haven't had a problem with them, but I've only had them in mature, well established tanks. Pristine water helps a lot. Neat fish, I like them a lot.
