Hey y’all so I have a 30 gallon DT it has been running for 7 months. I started off with weekly water changes because I have a HOB filter. I currently have 6 fish in total. I am now trying to switch to a 3-4 week water change where I will change 20% of the water. I am concerned about my decision and wonder what the consequences will be? I have tested water and nitrate is still below .1 ppm. Thoughts?