question on water changes

so far i have been changing half the water with the siphon every week. i have a small siphon and i do not think it is getting the job done and may go up to a medium size soon. i have changed the water 3 times now and it is starting to get a ton of particles in it when i stir up the gravel while changing it out, and i am wondering if that is normal and it will settle? will eventually need to do an almost full water change at some point. it is almost time to replace my filter as well, as it need to do it once a month. will having a bigger siphon help?