We have an automatic cleaner that works great in the pool - but we have a four foot tanning ledge than two steps that go all the way across the pool - This area does not get cleaned by the automatic cleaner.. we have tried sweeping the dirt off the ledge and steps but it seems to just stir up the water and eventually settles back on the ledge/steps. The ledge is too shallow for the manual cleaner to work - Any suggestions?