starting new hot tub with BBB method

[Dee]

Hi ya'll! I've been reading your posts for months as a guest and have learned alot as a new pool owner. I've already switched to BBB for my new pool this summer and had great success (much to PB dismay since I'm not buying all their chemicals). I'm going to be a new hot tub owner (Caldera Aventine - 150 gallons) this Wednesday and would like to use BBB with it also. Spa comes with a month's supply of chemicals. I would like some start up information and advice using BBB before the spa dealer tries to get me to use their chemicals. Any and all information, advice, tips, etc. will be appreciated. As I understand it if I use bromine I'll have to drain and refill tub to switch to chlorine and with the severe drought we are having (I have a well) that is really not an option right now. Instructions say balance alk (I'm thinking: add baking soda), then pH (thinking: add borax), calcium (unsure what to use here) then shock with chlorine (thinking: add bleach). I'm also wondering if I can use the Pool Calculator when doing the math for the BBB for the hot tub. Thanks in advance to all you great people for the help I have already received with my pool and all the information I'll need for the new hot tub.

IG 16'x32'x8' (17,829 gal.)
Hayward Sand Filter
Hayward 1 HP Pump
1 Skimmer

 

[JasonLion]

Welcome to TFP!

You seem to have the basics down. Most people use calcium chloride dihydrate, usually labeled calcium increaser or something similar, to increase calcium levels. When starting up a hot tub it is common to use dichlor for a little while so you get some CYA in the spa and then switch to bleach so the CYA level doesn't get too high. My Pool Calculator only reports quantities to the nearest ounce, which may not always be accurate enough for the small quantities used in a hot tub. What you can do, if a quantity is below say 5 oz, is to tell it that the spa is ten or one hundred times as large as it really is, and then divide the result by ten or one hundred. It is common to need to replace the water in a spa every three or four months. With care you can go longer than that but I wouldn't count on the water lasting forever.

Bromine is usually easier to manage then chlorine if the spa is indoors, but isn't really suitable for outdoor spas (unless they are almost always covered). Though bromine does have a noticeable chemical smell and some people are sensitive to it.

 

[giulietta1]

As I understand it if I use bromine I'll have to drain and refill tub to switch to chlorine and with the severe drought we are having (I have a well) that is really not an option right now.

Yes, that's correct. If you start with chlorine, tho, you can go to bromine w/o draining. So starting w/chlorine is a good idea; it's easy to go to bromine if you don't like the chlorine. The other way is problematic.

Instructions say balance alk (I'm thinking: add baking soda), then pH (thinking: add borax), calcium (unsure what to use here) then shock with chlorine (thinking: add bleach).

Baking soda is good for RAISING alk, but lowering it is more complicated! My source water has high alk, so upon each fill I must add dry acid, aerate, test, repeat as necessary until alk is 180 or lower. You must use dry acid (sodium bisulfate) to lower pH in a spa, not muriatic acid.

I have hard water so I've never had to add calcium.

Spa pH tends to run high b/c the aerating action of the jets causes carbon dioxide outgassing, releasing carbonate alkalinity and thus raising pH. I may not have described the mechanism entirely correctly, but spas typically have a rising pH/falling alk issue. Not a really big deal, just something you should know about. Make sure you keep dry acid on hand. It's a granular product often labeled "pH Down" or "pH Minus." Dissolve it in a bucket of water before adding it to the spa.

One cup of baking soda is about 8.75 oz, so one tablespoon is about 1/2 oz. One tablespoon of dry acid is about 3/4 oz. Buy some cheap measuring spoons from Wal-mart or from a thrift shop, and keep them with your spa chemicals.

An enzyme treatment such as Spa Perfect or Scumbuster is almost essential for spas. Use a scum-absorbing sponge also, like a scumball/scumbug or Zorbo. Shock weekly, more often at times of heavy usage. Replenish your enzyme a day after shocking, once your sanitizer levels have dropped back to normal.

Good luck and enjoy your spa!! I love mine.

 

[giulietta1]

I'm going to be a new hot tub owner (Caldera Aventine - 150 gallons) . . .

It occured to me that you will be using VERY small amounts of bleach to chlorinate such a small tub. Mine is 500 gallons and I use 10 oz of bleach--to SHOCK! That means your shock amount would be around 3-5 oz. Not really a measurement problem there, but for normal levels you might have trouble getting an accurate measurement.

So my idea was, keep a CLEARLY LABELED bottle of diluted bleach for your hot tub. Maybe a 10% bleach solution (9 parts water to 1 part ultra bleach) would be about right--that way, about 5 oz of the diluted bleach would give you 5 ppm in your spa.

 

[Dee]

Thank you for all the helpful and useful information. Are the dry acid (sodium bisulfate), calcium dihydrate (calcium increaser), enzyme treatment and scumball items that must be bought at hot tub/spa store or are they available elsewhere?

 

[JasonLion]

Yes, all of those are pretty much pool store or hot tub store items. Instead of dry acid I prefer to use muriatic acid, available at hardware stores, but it is a bit difficult to handle. Instead of calcium chloride dihydrate you can use calcium chloride, which is sold some places as a high end deicer, but it has gotten to be very difficult to find it with sufficient purity for pool/hot tub use (deicing is fine with significant impurities).

 

[giulietta1]

Yes, all of those are pretty much pool store or hot tub store items. Instead of dry acid I prefer to use muriatic acid. . .

Jason, you use muriatic acid in a spa? I've been told NOT to do that, that it's too "strong" for a spa. I don't entirely understand that, b/c if you dilute it substantially before adding it, it seems to me that there wouldn't be a problem. I would really prefer to use muriatic instead of the dry acid; fewer chemicals to buy is a good thing!

So Jason, if you tell me it's okay to use MA in my spa, I will start using it after I run out of dry acid!

Dee, the scum-absorbing sponges and enzyme treatments can be found in many online pool stores. I buy mine online at Spa Depot (www.spadepot.com); this store has an inexpensive enzyme treatment called Scumbuster. It works very well for me; I also like the Zorbo scum absorber, partly b/c it has a nice handy loop. Spa Depot also has the latex sponges (scumballs and scumbugs).

I believe many or most of the spa product lines have an enzyme treatment, so shop around to find a good price. Do make sure to note the dosage; you will want to consider the price per treatment, not just the price per ounce.

Enzymes are optional but very helpful in a spa, more so than in a pool.

HTH!

 

[Dee]

I agree with "fewer chemicals to buy is a good thing". I'm hoping the dealer will have an option of start-up chemicals -- chlorine vs. bromine. Thanks for the heads up on the Spa Depot -- I checked it out and figure what doesn't come with the hot tub can be got there with all the info I have received from you guys so far. Well, tomorrow is the day -- wet test and all! I've done what I feel is extensive research and have narrowed it down to the Caldera Adventine -- based on my needs, a certain criterion I formed after alot of reading and what is available in my area. This is a major purchase and I would welcome any last words of advice on purchasing a hot tub.

 

[JasonLion]

It is very easy to over do it with muriatic acid in a spa, particularly as the quantities involved are fairly small. It's a good idea to pre-dilute the muriatic acid substantially, say four to one (water to acid), or even nine to one, and then use that. That makes handling and measuring much simpler. It's not for everyone, but with appropriate care it can be used.

 

[giulietta1]

It is very easy to over do it with muriatic acid in a spa, particularly as the quantities involved are fairly small. It's a good idea to pre-dilute the muriatic acid substantially. . .It's not for everyone, but with appropriate care it can be used.

Thanks, Jason! Yes, I do realize that a small measurement error can make a big difference when one is dealing with a spa rather than a pool. When you dilute the acid with water, does it stay mixed, or does one have to swirl or shake the container before dispensing?

I assume it would it be fine to store the diluted acid in a used jug of muriatic. . . of course I do know to add the acid to the water, never the other way around.

 

[JasonLion]

It stays well mixed.