Lots of Pollen --- should I concern myself with phosphates?

[gilbee]

In our backyard, we have two large oak trees, and 5 crepemyrtle trees/bushes that are around the pool. While they are attractive, they dump a lot of stuff into the pool. We cut back the oak branches, and that has significantly reduced the oak leaves that make it in there, but these crepemyrtles are dumping junk into the pool all the time. I have a 5 gallon bucket I keep by the pool to empty the skimmer baskets and such, and last week I filled a bucket with mostly just the little crepemyrtle flowers! That said, while the flowers make their way into the skimmer basket, the pollen sinks to the floor, where the polaris picks it up. Every day or two, I can expect to pull up the polaris bag and have a baseball sized clump of what appears to be pollen.

I've read mention on here that pollen has caused some pool owners to give some thought to phosphates or other things that we don't conventionally think about in the TFP method, should I worry about these at all? The pool is clear, balanced, and beautiful now, just wouldn't want something I'm not testing for to come back and bite me later.

 

[JoyfulNoise]

You answered your own question - your water is clean, clear and balanced. End of story.

If you were to have recurrent algae blooms when keeping the FC levels at target or higher, then you might need to consider other sources of problems and more intricate solutions. But that is not the case.

One problem with phosphates is that there is no a-priori value for what is good or bad. The 100ppb limit is based on algae growth in waste water discharges but not on residential pool water. So, for some folks, they can have 1000's of ppb's in phosphates and never suffer a problem. Some folks could be as low as 200ppb and have problems. So even if you test for it, there's no bright line to say what is good or bad.

So, in the end, keep your water clean, clear and properly chlorinated and you will be fine. Ignore phosphates.


Sent from my iPhone using Tapatalk

 

[eqbob]

I have perhaps a similar situation, although it's knockout roses which surround nearly half the pool, society garlic, and decorative grass. Plus, we have no decking around the pool, just landscaping, so mower clippings can get in when mowing around the steps in, etc. Like you, the pool suffers terribly from sparklyitis. I originally was treating for phosphates (which isn't cheap) but that was back when I was listening to pool store and not following TFP. I have a phosphate test kit and occasionally test for the fun of playing with it and don't see anything that concerns me. Haven't done it in a while. I can honestly say that I never noticed a single thing different about the looks, feels, tastes, consumption of chemicals, operations, or anything else of the pool when it tested high in phosphates vs. none. I asked a lot of questions about phosphates in the beginning believe it to be a problem. The answers were don't worry about it which is appalling to an OCD engineer, but time has proven that to be the right answer. Either that or I'm getting horrifically poisoned by them and don't know it <G>

If you're really curious, get the Taylor test fit for it and check. But doubtful it's causing any kind of problem from my range of knowledge and experience (Which is certainly way less than other members)

 

[chem geek]

If you get to higher phosphate levels like the 3000+ ppb I had in my pool at one time, you would definitely notice a difference IF the FC/CYA level got too low. With plenty of algae nutrients, once you dip too low you'd notice chlorine consumption increasing so instead of the same percentage loss of FC per day that rate would increase and if you let it go the chlorine would get all the way to zero in a day or two. Algae would grow enough to turn the water dull to cloudy or have visible green clumps. This early stage of increased chlorine demand is what one sees in SWCG pools when their FC/CYA gets too low and the pool is rich in algae nutrients -- the algae is not yet visible but the chlorine demand is there and the pool seems unable to hold chlorine.

When algae nutrient levels are low, such as towards 100 ppb or so, the pool is no longer "reactive". If you let the chlorine level drop it will do so proportionately so while the percentage is the same each day as it gets lower it's a smaller absolute FC drop and it doesn't "crash" quickly as it does when algae is growing. The water remains clear.

Note that the difference I describe above only shows up if the FC/CYA level gets low enough for algae to grow faster than chlorine can kill it (or near that rate) in the higher nutrient scenario. So if you consistently maintain the proper FC/CYA level you will never see the effects of high algae nutrient levels. This is why I always say that phosphate removers should be seen in the same vein as algaecides. They are insurance (at extra cost) if one is not able to maintain a consistent FC/CYA level. They are not necessary.

The only other time where either algaecides or phosphate removers might be useful is in a situation where one is unable to eradicate yellow/mustard algae because it needs a higher FC/CYA level to kill it (compared to green and black algae) when nutrient levels are high. Another situation would be if one wanted a lower FC/CYA level and lower daily chlorine usage for whatever reason. One would need to trade off the higher cost of the supplements vs. the lower cost of chlorine at the lower FC/CYA level. Algaecide is also useful for temporary situations where the chlorine is intentionally brought to zero as with metal treatment with ascorbic acid or other reducing agents (e.g. citric acid).