Pool Details (as requested)

[aylad]

I would think that salt is a lot cheaper than bromine to operate, if you don't count the initial cost of the equipment and starting doses of salt and chems to get the chemistry right. With a SWCG, you're basically looking at muriatic acid to control pH, salt to maintain your levels, and occasional doses of bleach IF you need to shock. Those things, compared with the cost of bromine, are MUCH cheaper.

However, I don't know about what's necessary to convert from bromine to chlorine, so I'm going to let Pooldoc, Waterbear, chemgeek, or one of the others familiar with bromine systems address those questions. The forum is extremely busy this time of year, so it may take up to a few days before one of them pops into this thread, but be patient--they will come!!

[Cybergy]

Thanks aylad,

I spend about $300/season on bromine (+ baking soda). I'm thinking a SWCG at $900 should pay for itself in 3-4 years so as long as we don't plan on moving, it makes sense financially.

[aylad]

Watermom has asked Ben (Pooldoc) to take a look at this thread and he should be able to give you the necessary info about the bromine.

[PoolDoc]

Hi Rob;

I wouldn't get into a hurry. If you are spending $300/season for bromine, you probably aren't going to save enough to pay for the SWCGs. Some what you've been told is mistaken, but some is not.

In particular, if you've been using sodium bromide with chlorine or something else as an 'activator', it will be enough to drain most of your water and replace it. But, if you've been using bromine tabs -- BCDMH; bromo-chloro-dimethyl hydantoin -- you pretty much need to drain 105% of your pool's water. As best we can tell, DHM (dimethyl hydantoin) greatly reduces the rate of conversion of bromine to bromate (stable, non-actor in pool chemistry). And draining a vinyl pool that completely is both tricky and risky.

Here's a quick rundown on SWCG's
+ provide a stable and effective method of continually adding chlorine to a pool.
+ reduce likelihood of algae, due to constant chlorine feed.
+ reduce the need to store hazardous chemicals with damaging fumes
+ can be somewhat easier to operate
+ make it much easier to leave the pool for a few days, or go on vacation.
BUT
- cost more than you think for salt & electricity
- often require expensive cell replacement every 2 - 4 years
- can result in salt corrosion or damage, especially of natural deck stone
- require controlling calcium levels more tightly than you may have done
- often bring a continuing upward pressure on pH levels.
- only work well when the pool is operating normally; you'll need to switch to manual operation during start-up or algae episodes.

If I were you, I'd try to do a switch to chlorine + stabilizer this year, and think about an SWCG -- possibly after a 2nd drain and replace -- next year.

You can do a 95% in place drain of a vinyl pool, if you get a winter cover that is 16' oversize in both directions.

[Cybergy]

Thank you for your detailed response Pooldoc. You've given me a great deal to think about.

If I were you, I'd try to do a switch to chlorine + stabilizer this year, and think about an SWCG -- possibly after a 2nd drain and replace -- next year.

We moved to bromine from chlorine years ago because my daughter was showing some allergic symptoms when she was in the pool (mostly sneezing), so I can't see a move to chlorine being welcomed by the family ;-)
I think I'll just stay the course with bromine.