Switch Sanitizers at Pool Closing or Opening

[PoolDoc]

I've seen reports that suggest that the residue from degraded PHMB accumulates and eventually becomes irritating. So, if you've used Baquacil for 7 years, you've very likely reached that point.

There are a couple of things you need to consider.

First, when you replace your cartridge, you'll want to be sure to get a Filbur or Unicel brand -- or OEM -- cartridge, and NOT a Pleatco or other Asian made replacement. If you'll post your exact filter make and model, I'll see if I can help you find a replacement. The online descriptions can be very tricky, since the people selling Pleatco, etc try very hard to present their products as 'just as good' but cheaper, and in the process, often use some very misleading descriptions.

Second, as Dave noted, draining even an above ground can be risky. If you have a soft side pool (Intex, etc) it shouldn't be a problem. But with a steel wall pool, I would recommend leaving at least 6" of water in the pool. Unfortunately, if you do so, there will *STILL* be a bit of a conversion process.

But, straight chlorine bleach should take care of it. Just use your OLD cartridge, while starting up, and switch to the new one once conversion is complete.

[enahs]

To both BigDave and PoolDoc, before these replies I said "screw it"...I am draining it. So I did, I didn't have any issues as far as my one-time pool ownership expeirence person would know. I actually drained every last drop and used a rag to clean the whole interior of the pool. I am very anal about something like this considering I had so many issues. With that said the 8,000gal AG pool was drained and refilled all within a 24hr period. I have a propane heater that I only use under certain circumstances so I was able to raise the temp from 70F to 83F the next day. I got my chlorine levels up to 3 the day after filling and it has never been nor could it be clearer. Oh and it remained clear after adding the first 8oz dose of chlorine so I am pretty certain all the biguinide was removed from the liner and all other parts that were involved.

As for the filter, against my better judgment and research I used the same filter I had been using with PHMB. It is a 120 sq/ft cartridge filter with a 1.5HP pump (yes I know crazy equipment for this size of pool but, hey, I got a good deal.) With that said I still had and have an unbelievably clear pool. I honestly feel like I have never had this clear of a pool after my first year (or second) when started PHMB. I researched my filter size to find Filbur or Unicel brands. I got to a point where I could not find either of those brands in my size filter need. The local pool store had a sale that ultimately provided me a Hydromatic (my filter brand) filter of BYOG, or a total price of $110 for two filters. Another local store had a Black Diamond (same filter I currently have) for $85. I decided on going the BYOG route since I would hope my filter replacement timeline would be much less than previously. I have literally had 3 filter cartridges in less than 2 full pool seasons here in western PA. Thanks to biguinide as I have a better understanding on how it works.

Anyway, two questions from this:

Why are you saying that you should not drain an AG pool? I mean it was empty before the installer filled it. One thing this helped me do was there were a couple of areas on the bottom of the pool (against the wall) that were "pits". I was able to rub the liner to an extent where I fixed those issues. They bugged the crap out of me...

What is the difference between Unicel, Filbuer, Black Diamond and Pleatco filters? I was told that all of these mfgs (maybe not including Black Diamond) make filters with 3 levels of material so all three could, essentially, be equal. The Black Diamond was nice because there were less ribs but thicker material (essentiall providing the same square footage of filtration) but easier to clean. I have never used Unicel, Pleatco nor Filbur. I have only used the OEM (Hydromatic) filters.

To end I have had a ridiculously clear pool since switching...I understand that there have only been a couple of times with people in the pool but we have also had some good rains. I was going to go the BBB route but with such a small pool and having had enough of dealing with my issues with PHMB I decided to just do straight chlorine. Figured with a good test kit and paying as much attention as I do to it I should be able to keep a good 2PPM chlorine level and 7.5 pH level. I'll see if I want to change to a slat water pool two seasons from now.

[BigDave]

Congrats, glad it worked out.
BBB is straight chlorine. BBB is a bit of a mis-nomer but the best name we have. What's really taught here is a safe, effective, and efficient method of pool care based on science and proved by experience. The method requires involvement: You test the water so you can trust the results. You decide what and how much to add to the water to keep it in range and you measure the results. You learn how your pool reacts to chemistry, swimmers, weather and you'll be ready to respond. Let's keep you new water clean, let us know how you're sanitizing now, and a full set of test results from a K-2006 (calcium probably doesn't matter much but it wouldn't hurt to get a baseline).
Read the Best Guess Chart from Ben's sig - it explains alot.
Did you order a K-2006 (or K-2006C) yet?