Stephanie - at times under certain conditions a pond can develop abundant greenish colored algae that usually floats and forms scummy films downwind similar looking to thick heavy bath tub floating soap scum only green and denser - thicker. Some of these algae when injested by a dog licking its fur or drinking the water can make the dog sick and occassionally the dog may die after being quite sick. Caution is the plan for allowing the dogs to swim when the pond has abundant floating thin films or scums of greenish grainny algae. This harmful algae is not the type in mats-clumps-wads nor is it in stringy floating green clumps (string algae aka filamentous algae FA), both common in ponds and rarely toxic.
Three of the most common problems with a windmill not producing air bubbles are 1. the diaphragm is worn, cracked and or split - replace it. 2. the underwater bubbler (diffuser) is all clogged up and holes in it plugged shut - (cleaning needed), 3. the check valves (often 2) in the head of the windmill are dirty & not working properly and need to be replaced - often done when the diaphragm is replaced. Windmills need regular maintenance.
Last edited by Bill Cody; 02/15/12 02:50 PM.
