Algae eater for cichlid tank

I have had a 125 set up for 5 months now and am still having problems with brown algae and hydra. I do a water change every week and make sure I do not overfeed. I am wondering if an algae eater of some sort would be helpful. I have 5 cichlids and 5 giant danios in the tank. It should also be known that my ph is off the charts due to my well water. I have never had green algae at all and my water has never been clear because of all the brown algae that is floating around. I am getting frustrated. So if anyone has any suggestions let me know. I just do not want a algae eater that gets two feet long. thanks.