A lot of times my toilet will decide not to flush with only one flush. Sometimes it’s two or even three flushes. It really doesn’t matter how much waste is in the toilet. Other times it flushes like a dream. I have tried moving the chain (actually a plastic strap) up or down to change things. It doesn’t work. I have a brick in the tank. No additional help from that. I wouldn’t be as concern with this normally, but I have a family of 5, and a 1000 gallon septic tank that fills up more than it should. I have drained the septic tank and put acid treatment in the box. So far it’s been working well. I had back up originally and went to the septic tank for answers. Now I am trying to deal with my toilet. Can anyone help me? Please?!?