I have started with a 3gal 5months ago then I just got a 20gal. So I'm some what new. Just found out I need to be testing the water. I been doing 20% water changes. I bought the test strips to start just can't swing $30 for the nice kit. So I tested the water and nitrate , ammonia and gh are low but my kh and ph is off the chart in both tanks. How do I get them down. In my small tank I did a 50% water change yesterday and added just distill water and still no change to it.