nhlcreation

I work at a school that gets their internet from a wireless provider. The isp's antennas are on the water tower no more than 100 yards away. Right now the school has an omni antenna just attached to the roof. We have problems with drop outs and slow speeds daily. My question is, given the radiation pattern of an omni antenna and the schools relatively short distance from the water tower, do you think I could replace the school's omni antenna with something like a panel antenna pointed at the water tower and that would help? Any help would be greatly appreciated.