Unfortunately, if you haven’t paid much attention to it over the winter, your pool may be a little out of control. Remember, the pool has absorbed dust, pollen, and all other sorts of material since it was too cold to swim. If you’ve started to see water quality problems, don’t fret! Here are some common problems, and fairly easy solutions.
Mustard algae is usually found on the shady side of the pool in “sheets”. I’ve also seen it start many times in the spa, and then spread to the pool. This type of algae has frustrated many homeowners through its propensity to go away, come back, go away, etc. Again, strong shocking, brushing, and using more filtration is the fix. A preventative algaecide will help keep it from coming back, as will extended filtration cycles. If possible, keep birds, dogs, and other wildlife out of the pool, as this is a common means of diminishing your chlorine level. I also believe it isn’t a good idea to wear a swimsuit in the lake and then use it in the pool – there are too many “things” in the lake that you can actually reintroduce into your pool, making pool maintenance harder.
Ask any pool pro about this one, and you’ll get a shudder. Black algae starts as a small black or dark green spot, and spreads rapidly around the pool. You’ll see it first near lights, jets, corners, or in the tile grout. While not impossible to remove, it requires a very different approach than green or mustard algae.