Algaecide

[PoolJunkie]

I have been using maintenance doses of algaecide as recommended by the company that installed our pool, but after reading all the info here regarding the BBB method, it seems that there may be no need for it at all. Does chlorine adequately prevent algae if the chemistries are kept in good balance? Do any of you guys routinely use algaecide?

[CarlD]

There are only two algaecides we recommend: The first is, of course, chlorine, administered properly. The other has many names but is Polyquat 60%. If the only ingredient is "Poly....<something long and unpronounceable> ... 60% and the rest is "inert ingredients" that's the stuff. It's much better as an algae preventer and helps clarify the water. You don't have to use it but a weekly dose of an ounce or two can help prevent algae.

Every other algaecide is more likely to do more harm than good.

[PoolJunkie]

If I follow the BBB method closely, do I need to be putting a maintenance dose of algaecide in weekly? Does anyone here advocate for that? I have noticed that it causes foaming, and it sounds like regular shock should be just as good at keeping algae at bay.

Also, I recently bought new 3" chlorinating tabs. The ones I got from the pool builder were trichlor-CYA and just ran out. The new ones are "HTH Super", are also a tri-chlor but also include zinc and algaecide. I had no idea they were different when I bought them. From what I have read here, I may want to just return those. I am starting to believe the mantra that I should not be putting anything in there that doesn't need to be there.

18500 gallon fiberglass pool with heat pump, pentair C400 filter, variable speed pump.

[CarlD]

For just the reason you describe we do NOT recommend most algaecides, ever. The ONLY one we suggest using is Polyquat 60%. Its ONLY active ingredient should be "Poly...<something long and unpronounceable>...60%". It make be called Black Algaecide, Mustard Algae control, whatever. Only the ingredient matters. It does not foam but it can inhibit algae growth.

We also STRONGLY discourage using things like the HTH Super you describe. You want to use Tri-chlor with a 99% purity. Tri-chlor by its nature is highly acidic and adds stabilizer (CYA), which, if you need it, is good. If you don't, it's bad. But with "zinc and algaecide" is VERY, VERY BAD! I believe HTH knows it but doesn't care and sells it anyway because it LOOKS important and will get you to buy it. That's my opinion.

We think "cocktail" chemicals from pool companies only get you in trouble and empty your wallet.

Our FIRST and last recommendation for chlorine is....bleach. In certain situations we will recommend Cal-Hypo, Di-chlor powder, or tri-chlor tablets. But generally, bleach or its stronger sibling, liquid chlorine are best.

[Watermom]

No need to start a second thread. Let's keep the discussion all together in one thread. ( I merged your two threads into this one.)

Welcome to the Pool Forum!

[CarlD]

Thanks, Lisa. I didn't realize the user had started two threads--I only saw one post in the post count.

Pooljunkie, that's why we ask that you don't start duplicate threads. I wasted time typing the same thing twice.

[PoolJunkie]

No need to start a second thread. Let's keep the discussion all together in one thread. ( I merged your two threads into this one.)

Welcome to the Pool Forum!

Thank you, I didn;t realize there was a delay and thought maybe I hadn't clicked submit on the first one.

Thanks for the feedback, the "HTH Super" will go back to the store tomorrow and I will find the Tri-chlor! Tri-chlor was what I used all summer and my CYA levels are in range. I will watch them next year to make sure they don't get higher. I have an in-line flow controlled cylinder for the tablets so I can fine tune the baseline chlorination and CYA, then shock as needed.

As for Algaecide, I just found another gem on this site and figured out why I had to shock my pool 4 times on Sunday just to get a measureable FC level . . . I put in a treatment dose of Algaecide on Friday (NOT polyquat, cant remember the long name) and it was probably eating the chlorine.

[CarlD]

Polyquat will lower your FC if used in large amounts, but not in small weekly doses. When I close my pool, I run FC up to shock level and add a quart of polyquat, then wait 48 hours. FC drops like a stone, but then I raise it back to shock level and I am done with the water.

[Watermom]

Thank you, I didn;t realize there was a delay and thought maybe I hadn't clicked submit on the first one.

When new members write a post, it goes into a moderation queue where it waits until we read it and approve before it is modded in and will appear on the forum. We try and empty out the queue multiple times per day so usually it isn't too long before it will show up. :)