Pond Boss Forums GENERAL QUESTIONS Muddy water Understanding the Causes of Secchi Disk Readings

Now I understand your question. Again, the answer depends on why your testing. Lets say you have an irrigation reservoir that your want to treat. An irrigation manager wants the water as close to crystal clear distilled water as possible so that the suspended and dissolved solids do not clog filters, emmiters, etc... However, if you are trying to create fish habitat you want a healthy balance of planktonic algae and other things for fish to graze on. In this case, your water will not be crystal clear. It will probably have a nice green cast to it with 2+ feet of visibility. To my knowledge, inorganic suspended solids do not really provide any service to your ecosystem aside from maybe blocking solar radiation therefore reducing weed growth (this is a stretch). This is a generalization of course. Site conditions, and other factors dictate how well you will be able to achieve your desired water clarity or quality. Maybe this would be a good topic to bring up in the fish stocking forum since there are probably more fisheries biologists that can tell you the values that would indicate a healthy population of algae.