black water

by Howie
(Plymouth,MA)

I have an Aquascape filtering system. My pond is approximately 3000 gal The past two years, my pond turns almost black in color. I haven't replaced the lava rocks nor the filtration pads for about 5 yrs. The ph, nitrates, and ammonia levels are fine. I live in southeast Massachusetts.
Thank you.

Doug says he also suspects you haven't cleaned the pond in a long time. Normally we want to give it a serious cleaning every 2-3 years - power washing the rocks down in the pond and getting rid of a lot of debris and "gunk" from the bottom. Some folks recommend a yearly cleaning if you have a lot of fish activity.

I'm not overly worried about decorative rock but you might want to check the condition of the filter material and see if it's plugged up or torn.