I suspect your filter is set up wrong. You should have no problems with a 200# sand filter and a 2sp 1 hp pump. Something's wrong and here are your choices:
1) your laterals are damaged in the tank.
2) your 6-way valve is defective or assembled incorrectly.
3) Your pump is attached to the filter backwards (intake where output should be)
4) You have too much or too little sand, or are not using filter sand.
5) Your pump is defective or installed wrong (assuming a new pump)

The basic filter is nothing more than a tank into which the laterals and the sand goes, so it's got to be one of the above.