Matrix's Rants

Saline Pool Systems sells and installs "Saline Systems" for swimming pools. They seem to want to sell ther products to un-aware customers. I say this because I have a client with a fiberglass swimming pool that currently has a bromine system. The thing is, on a bromine system where a saline system is installed, the saline system would have to run more continuously than it would have to on a non-bromine system. This means that the "salt cell" of the saline system wears out a lot sooner than normal. This would be ok if my client doesn't mind coughing up about $450 periodically everytime the salt cell burns out from over-use. Though I was told, after much research, that this particular unit sold by Saline Pool Systems has a very durable salt cell, I don't believe that this compnay informed my client thoroughly about the habbits of said products in general. The other point is that it wouldn't be a problem if we could just drain all the brominated water from the fiberglass pool, but fiberglass pools cannot be safely drained completely due to the nature of fiberglass pools being subject to collapsing without some water remaining in the shell. To rid all the bromine, the water would have to be completely drained since bromine just re-creates itself from "left-over" bromine ions. This is why it's so important to drain the brominated water completely.

There are some neat pool products out there that can be really useful. Unfortunately, some of these products have "gotcha's" that your dealer often won't mention. [He may not know, himself!]

And, while a product's 'gotcha' may not get you, it's nice to know up front, or at least I think so.

Possibly one of the worst offenders in this regard is bromine. Many swimming pool owners tend to think of bromine as something they can try, and then abandon at will.

Here it is: chlorine converts 'used up' bromine (bromide) back to free bromine, and in the process, is converted itself to 'used up' chlorine.

As a result, as long as even 2 or 3 ppm of bromide ions remain in the water, you CAN'T have a chlorinated pool. And since bromine can't be stabilized, you also CAN'T have a stabilized pool.

So read the label before you pour: if it says anything about 'bromine' or 'sodium bromide', think twice. Do you really want a brominated pool? If you do, pour away!

Sunlight can convert sanitizing bromine compounds into permanently inactive bromates. Also, some chemists claim that a portion of the bromide oxidized by chlorine is converted to inactive bromates, instead of sanitizing bromine compounds. So on an outdoor pool, which gets lots of sun, and which is shocked with chlorine, a long time may only be a few weeks, instead of months.

Complicated Note:

Jock Hamilton, president of United Chemical sells a line of pool specialty chemicals that are based on sodium bromide. He claims that bromide in pool water breaks down rapidly, rather than slowly. Apparently, he's right . . . at least for outdoor pools exposed to sunlight.

Let me state it this way: in pools exposed to sunlight, bromine persistence is usually a long-term problem ONLY if the pool is brominated with any form of bromine tabs!

If bromine has NEVER been added to an outdoor pools in the form of tabs, shocking the pool (5+ppm of chlorine in a single dose), added on sunny days, will tend to remove the bromine/bromide. However, repeated doses may be needed.

On all indoor pools, and on all pools treated with bromine tabs, the only practical way to remove the bromine is to drain the pool.

The difference seems to be DMH ( dimethyl hydantoin ), a molecule used as a chemical 'coat-hook' for BioLab to hang the bromine and chlorine when creating the solid form of bromine, BCDMH (bromo-chloro-dimethyl hydantoin), sold in the USA. After the chlorine and bromine are gone, the DMH hangs around, affecting water chemistry in a variety of unpublicized and mostly undesirable ways. If DMH is present, it is VERY hard to get rid of the bromide without draining the pool.