Dont know if you use FX series of filters, but you can get a vac that uses the FX pump to do all the work.
Good suggestion. Axolotls are salamander like creatures from Mexico that do not like water flow (I did not know what they were before my daughter fell in love with them). So we just have a sponge filter and corner filter in the tank. Neither really offer much in mechanical filtration but are good at biological without inducing a lot of flow.