Help

what can I do to maintain my water clean?

So I have to juvenile yellow sliders and I have been seen they have been shutting their skin which I have never seen them do before, but I have researched and it is very normal. I have never had problems with them and shedding their shell or scutes but with their skin, the water has been becoming kind of whitish cloudy..... I thought it was something else so I took some water out and cleaned the gravel with a gravel vacuum and added more clean water and it made the tank look really nice but not even a week after the water is cloudy again..... i have 2 20 gal tank and have 2 filters each since they are very messy.... on top of that, I have such a hard time cleaning because I am only 100 pounds and I have to literally climb on top of table because there's no way I can move their tank. Is there anything I can do? Can they stay in that cloudy water or should I be cleaning it more often?