Have your females been neutered? If not, he could have impregnated them already and they need doing ASAP! His peeing behaviour could be the beginnings of territorial marking, but could also be a sign of infection or urinary tract disease. It would be best if you could get a urine sample to take to the vets for analysis. Easier said than done, but I find a good way is to confine him with clean gravel or non-absorbant material in a small litter tray, that way you can get the urine out.