analog gurus, please help, cartridge too light?

dear gurus, i recently purchased a rega p25 tt with the rb600 arm. the tt was also purchased with a benz micro mc20e2 cartridge which i understand later is a very light cartridge with a weight of 4 grams total. my problem is that i cannot get the arm to balance even with the counterweight all the way forward and tracking force and the antiskate setting to zero. the arm still goes up quite a bit. should i change to a heavier cartridge? i am hoping not as i already paid for this one with the understanding that this cartridge is compatible with this arm. should i just set the tracking force and antiskate to zero and just use a stylus gauge and set the tracking to 2 grams as recommended? i read somewhere that the rega arm can be set to the max tracking to relieve some spring inside and then adjust the tracking force by the stylus gauge?with my setup right now, is the expressimo heavyweight out of the question? thanks for any comments. yes, i am a newbie. curtis.