fishin4cars
True friends just call me Larkin
Personally, I check weekly, This usually gives me a heads up that something is happening before it gets out of control. I keep a log book, each week I check the water, then make my water changes accordingly. If the nitrates are up or if I see and change in nitrites, I'll do a little bigger water change, I also monitor GH and KH weekly, If these two parameters start fluctuating you can count on PH fluctuations shortly there after if you don't get them back stable. This is usually a problem on older ponds than newer ponds, Newer ponds usually have more problems with Ammonia and Nitrite issues, Nitrates high are a sign of overfeeding, not enough filtration, heavy fish load, not enough water changes or a combination of any or all of these. O nitrate readings are rare to see, To maintain that pristine of water you have to be doing everything perfect and the fact of the matter is, few fish keepers really go to that extreme. Nitrates are formed from the breakdown of ammonia and nitrites which are constantly being produced. Which is why it's virtually impossible to read O unless you have Top of the line equipment, the most stringent maintance program, stock lightly, feed light, and do large water changes daily.