If your tank was completely cycled you would have o ammonia, o nitrite, and some nitraters. You said you clean your filter, how do you clean your filter? If the coagualnt stuff you put in your tank makes the water clear, then there may be something in your tank giving off particles. What is your cave made of? What kind of substrate do you have? Unless you are doing soemthing when you clean your tank to cause a bacterial bloom, which is a possibility since you do have ammonia in your tank water, it is possibly one of your tank decrations or your substrate giving off particles. Could it be algae, your nitrates are kind of high, not in the danger level but still high. Seeing how the clear right stuff, or whatever the name was it is a coagulant, worked I would kind of lean moer toward the free floating particles in your water.
One thing to add about using ph up, as the poster before me said stop using it, and i would never use it agin. The fish will acclimate to whatever your ph is, its better for it to be low and stable, than to be fluctuating all the time. If you must have a ph of 7 use seachems neutral regulator, it has buffers in it to buffer your water so it can maintain a stable ph of 7. You just put in in the water until you reach 7 and then when you do watr cahnges add the amt the bottel says to each gallon you put back.