I'm in the process of switching from Baqua Spa products to dichlor. I have a 350 gal Leisure bay. This what I have done / plan to do -
- reconnected my ozonater
- drain and fill
- added 5 tsp dichlor to shock and ran overnight
- drain and fill
- replace filter
- balance PH to ~ 7.5
- add 3 tsp dichlor at startup and once per week
- add 1 tsp dichlor per use
- monitor and maintain PH (7.2 - 7.8.) and (free?) chlorine (1.5 - 3.0)

Sound OK? Am I missing anything?

sounds good but if your ozone is 24hr and a good quality CD version you won't need 1/4 of the chlorine

My spa is about 7 years old, and I think my ozonator is the type with a bulb in it and not CD. It is 24 hr though. Can I still cut down on the dichlor? If yes, how much per use and how much per week? We use it about 3 times per week with 2 bathers. What should be the chlorine range I maintain? Should I be monitoring total chlorine of free chlorine? Thanks for the help.

you need a new ozonator - upgrade to CD
UV lamps have an effective life of up to 3 years - their output typically drops off to approx 50% after 100 hrs (4 days!) and then slowly erodes away to approx 30% at around 3 years. it's at this point that the ozone concentration is no longer adequate to be of benefit - 2 choices (the first one being bad, but cheaper!) - replace the lamp (and starter if fitted) or upgrade to CD which in most cases has no drop off in performance until it dies. On top of that - they produce greater levels of ozone at higher concentration.
(figures above are debateable - different sources quote differnet values, but the general point of the argument is the same)

I'll probably go with the CD option. Searching a little I found the Del Eclipse for about $90, is that a good brand and price? I know I have an AMP plug, but how do I find out if I need a 120V or 240V? Is it fairly simple to remove the old one and install the new one? Also it looks like there is a $50 chip that needs to be replaced about once a year (9000 hours) is that normal for a CD ozonator?

this is a cheaper CD ozonator - pick one that operates with a high voltage 'lightning storm' uses a high voltage transformer and spark chamber - spark generator - known by a lot of different names - sorry, can't assist with model - we have del mcd50 which go by other names in USA - awesome unit - haven't seen any fail for 7 years yet.

It looks like I'll be switching back to Baqua and disconnecting the ozonator after all. After two short soaks I've started getting the rash that caused me to switch to Baqua in the first place. I was hoping to avoid the rash using a small amount of dichlor instead of the bromine and MPS shock that I used to use. Thanks for your help.

Have you tried silver with your ozone? It works well, doesn't cause rashes, and is a lot less work than using Baqua.

My 2 cents

Some people are actually allergic to ozone and can get rashes from it. It might not be the chlorine or bromine causing your rash?
You can test each by rubbing a little on your for arm to see if you get a rash.

If you do change back then you might want to also replace your filter.

As far as cd verse uv goes.......Alacy has made some good true points on the cd type. However I would be more apt to replace the uv back with a uv on a Leisure Bay Tub considering the way it's plumbed. My concern would be the total solubility of the ozone gas. I think you would be creating more off gas then desired on this system. Defiantly do not even consider it if you have a indoor installation. It would be ok if your spa install is outdoors and if you want to do some modification to the plumbing to assure proper mixing and depletion of the gas. I use uv ozone with 1 ppm bromine and a little chlorine shock on a leisure bay tub. No problems

The biggest problem I see however is the your trying to use a polymeric biguanide on a spa maybe not designed to handle it pending the year make and model. If it's a 24 hr filtration model with a mechanical pack then I don't think there are any filtration stir cycles or pump timers. Again a solubility problem. The grundfus pump doesn't have enough unff to keep things from precipitating like the calcium your going to have to add to keep the biguanide from foaming and the water balanced. It has a good turn over rate for a spa but every low psi. It's normally used with a uv ozone to produce good o2 to o3 transitions. Also the plastics on the spa like the light lens's may just crack or get mushy and leak over time....plus a few other things my go bad.........anyway good luck Pork

mogmios - Yes, at one point I tried one of the silver based systems, but I still got the rash.

Pork - (are you related to Swine?) Allergic to ozone? Now that is one thing I didn't consider. It's never made sense to me that I can spend all day in a chlorinated pool and not get a rash, but 15 minutes in my slightly chlorinated tub and I'm itching all over. I may have to try switching back to dichlor with the ozonator disconnected. Thanks for the tip. If there is any way I can stop shelling out the big $$ for Baqua, I'll try it.

polymeric biguanide = BaquaSpa sanitizer, right? Are you saying my tub may not be able to handle BaquaSpa? I've got a 1999 19300-S series Leisure Bay. It has 24 hour filtration and once a day it kicks into a full jets on, bubbles on cycle (is this a stir cycle?). Our water is relatively hard, so I only add a small amount of calcium. I've been running BaquaSpa for about 5 years now with pretty good results.