Pollen Mistaken as Algae?


Well-known member
Jul 23, 2012
Dallas Ft Worth
I keep my SWG North Texas (Ft Worth) pool open year round. I have no backyard trees. My vegetation surrounding my pool is Crepe Myrtle and Red Tip Photinia. After a winter of keeping up with my pool and having decently balanced chemicals I noticed this past week a yellow/greenish growth on my vertical pool surface in one end of the pool.

My wife works with several local cities as a swim instructor and one of the city pool guys claims Crepe Myrtle pollen can attach to pool walls and look like mustard algae.

Anyone ever hear of this? Just curious. My Crepe Myrtles have started growing from winter dormancy and this end of the pool DOES have 3 near by.
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Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Can't say I've heard of that myself. I have quite a few Crapes in my yard as well (bloomed last month), along with about 90 Red Tips and more. But never had any such items shed blossoms and try to hold onto the side of the pool. Hit the water and sink sure, but not stay vertical. That seems a bit odd to me. Would you like to post a full set of test results for us to look at? Maybe we'll see something from your TF-100 or Taylor K-2006 tests that will give us a clue?


LifeTime Supporter
Nov 26, 2013
Trees which are pollinated by bees (they have pretty flowers) don't produce much pollen. However, those pollinated by wind produce insane amounts. Given our live oaks just finished up, I'd assume the live oaks in North Texas are still going crazy right now. You don't need them in your yard to have lots blow into your pool. A quick look online shows maple and oak as high in Dallas.


Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
Sebring, Florida
Brush the suspect material up into the pool water. If it's mustard algae, it will be back in a day or two in the same spot.

You would also be using extra chlorine to fight it. What is your chlorine consumption?


Well-known member
May 9, 2008
NE Florida
I have huge oaks over my pool and suffer that same problem every spring, I've never been convinced it is algae or pollen. The solution for me is the same either way. After they are pretty much done with pollen, I run the cl level up to 25 or so until it clears then vacuum a lot. I'm in that process now. I'm thinking it may be pollen because my my pool has been at 10ppm for a few days with no cc levels detected. I would suspect if algae, I'd be loosing more chlorine and have cc levels of some sort. Regardless, I've started the process of bleaching it all out.