Phosphates and DE Filter

[sjsoldo]

I know a lot of you may poo-poo this post; most of you probably feel that algae can be kept out of your pool without paying any attention to phosphates. Probably true, but for whatever reason my pool can still get yellow algae even with well maintained free chlorine levels, proper pH and periodic additions of bromine ("No-Mor Problems"). Phosphate binders seem to help, I use the the "Phos-Free" product from Natural Chemistry.


Here is my issue: Typically the phosphate binder is added to a recently cleaned filter via the skimmer. For a while after you add it, the filter pressure goes up and this requires more wattage for my variable flow pump. Sometimes the pressure stays up for quite a while and it is desirable to clean out the filter again.

Question: Does the effectiveness of the phosphate lowering product go away if you clean the filter too soon?

Thanks in advance.

 

[duraleigh]

most of you probably feel that algae can be kept out of your pool without paying any attention to phosphates. Probably true

But you have a need to use it? Why are you mixing bromine and chlorine in a pool?

 

[JasonLion]

I don't recommend using "No-Mor Problems", or any similar bromine based products. The bromine stays in the water for a long time and will continue to cause minor problems for months.

From your description it sounds like you have never killed off all of the yellow algae, and are simply holding it at bay. It would be much more effective to properly shock the pool and get rid of the yellow algae once and for all. There are instructions on how to properly shock for mustard algae (which requires extra steps) in Pool School.

Phosphate remover will only be trapped in the filter, and thus raise the pressure, if it is bound to phosphates, so backwashing/cleaning the filter is a good idea. That is assuming you are bothering to use phosphate remover, which we don't recommend.

 

[sjsoldo]

What are the "minor" problems that bromine can cause? It seems to be effective for preventing algae.

 

[chem geek]

We never said that the recommended FC/CYA levels would prevent yellow/mustard algae growth. Those levels are to prevent the far more common green algae and also to prevent black algae growth. Yellow/mustard algae needs higher FC/CYA levels (roughly double the minimum) to prevent its growth and since that can be impractical we normally recommend complete irradication. Though this isn't easy, it is doable in most cases.

The No-Mor-Problems turns your pool into a bromine pool. Bromine breaks down with the UV in sunlight and does not bind to CYA so you may find your chlorine usage go up during the day. Bromine can be harsher on swimsuits, skin and hair since it is not moderated in its strength and it smells different (technically the bromamines smell different) which some people do not like. The brominated organics are also more mutagenic/genotoxic though in residential pools this is a very low-risk issue compared to high bather-load commercial/public pools.