Maintaining Chemicals While On Vacation?

[Emprov]

I'm going on vacation for 11 days next month and I'm wondering what to do about the tub. Been thinking about getting a floater, filling it up with chlorine tabs and opening it up only slightly. Is that the thing to do or is there a better idea. How about lowering the temp to about 80 degrees and shocking right before I leave?

[chem geek]

The combination of lowering the temperature and not using the tub will have the chlorine last much longer. Even so, it won't last more than a few days unless the water is REALLY cold (< 60F). However, using a chlorine floater with Trichlor tabs has several problems. It will add CYA to the water, but that's not really so bad for a short time. It is very acidic, however, so if it added 2 ppm FC per day for 11 days, then the pH would drop from 7.5 to 7.2 if the TA were 100 (if it added 4 ppm FC per day, then the pH would be a little below 7.0). The main problem, is that it is hard to control the feeder to not add too much chlorine and that the feeder can park itself near an edge where the acidity of the Trichlor can concentrate when the pump isn't running.

You might be better off taking a small plastic bottle and filling it with bleach, perhaps half diluted with water (and mixed) and with a very narrow mouth or a cap that you've drilled a hole into. Then set this on the bottom with the open end up. Chlorine is heavier than water and will slowly diffuse out of the top and will be pre-diluted from the water that it mixes with (i.e. the concentrated chlorine stays near the bottom of the bottle since it is more dense). The only problem is that I don't know what size of an opening would be appropriate for a slow dosing over 11 days. If you aren't going on vacation right away, you can try an experiment to see what size opening keeps the FC roughly stable (say, between 1 and 4 ppm). You won't want to use the tub while this is happening and you'll want to make sure that the pump flow doesn't tip over the bottle.

See this thread for how this was done in a swimming pool. Obviously, for your hot tub, you need a far smaller amount of bleach. At 2 ppm FC per day over 11 days in 350 gallons, that would be 2 cups of 6% bleach or 1 quart of half-diluted bleach. A bleach jug is usually 96 ounces (3/4 gallons or 12 cups) so I wouldn't use a full one since you don't want to accidentally overdose. But if you have a spare jug and mix 2 cups of 6% bleach and the rest with water, then this might work.

Richard

[fdegree]

Dropping a container of diluted chlorine to the bottom of the spa is rather interesting.

What about vacationing and leaving a Bromine spa?

Using this same method would cause the chlorine to interact with the Bromine bank...would that keep the Bromine at shock level? Would an extended period at shock level cause any problems?

Since I have a Bromine floater, would you recommend just filling it with tablets and let it go?

Thanks!!!

[chem geek]

With Bromine, I would just recommend filling it with tablets if using BCDMH or similar dimethylhydantoin derivative combination that releases both bromine and chlorine. It's only if you are using sodium bromide tablets where you would need to have some sort of slow-release chlorine.

Richard

[Emprov]

\

You might be better off taking a small plastic bottle and filling it with bleach, perhaps half diluted with water (and mixed) and with a very narrow mouth or a cap that you've drilled a hole into. Then set this on the bottom with the open end up. Chlorine is heavier than water and will slowly diffuse out of the top and will be pre-diluted from the water that it mixes with (i.e. the concentrated chlorine stays near the bottom of the bottle since it is more dense). The only problem is that I don't know what size of an opening would be appropriate for a slow dosing over 11 days. If you aren't going on vacation right away, you can try an experiment to see what size opening keeps the FC roughly stable (say, between 1 and 4 ppm). You won't want to use the tub while this is happening and you'll want to make sure that the pump flow doesn't tip over the bottle.

See this thread for how this was done in a swimming pool. Obviously, for your hot tub, you need a far smaller amount of bleach. At 2 ppm FC per day over 11 days in 350 gallons, that would be 2 cups of 6% bleach or 1 quart of half-diluted bleach. A bleach jug is usually 96 ounces (3/4 gallons or 12 cups) so I wouldn't use a full one since you don't want to accidentally overdose. But if you have a spare jug and mix 2 cups of 6% bleach and the rest with water, then this might work.

Richard

That's an awesome idea, thanks. Perhaps a plastic quart milk jug with about a 1/2" hole drilled in the cab would do the trick?

Once again Chem geek, you da man! I'll have to do some experimentation over the next few weeks.

I can't use Bromine, Hot Springs says that I've got this silver coated thingy in my filter that doesn't like Bromine. So, I'm currently using Dichlor. Bleach would be a good fit?

[chem geek]

Bleach would be fine. In fact, you should probably be using bleach as your regular chlorine source anyway if you've already been using lots of Dichlor. Dichlor will add to CYA making chlorine less effective so you only need around 1-2 weeks worth of Dichlor after a fresh refill and can then switch to using bleach. For those worried about using a liquid such as bleach that can spill or splash, there's also Lithium hypochlorite powder that quickly dissolves (like Dichlor) but does not add to CYA. It's expensive, though, but for a spa, the quantities are low.

Richard

[B0Darc]

\

You might be better off taking a small plastic bottle and filling it with bleach, perhaps half diluted with water (and mixed) and with a very narrow mouth or a cap that you've drilled a hole into. Then set this on the bottom with the open end up. Chlorine is heavier than water and will slowly diffuse out of the top and will be pre-diluted from the water that it mixes with (i.e. the concentrated chlorine stays near the bottom of the bottle since it is more dense). The only problem is that I don't know what size of an opening would be appropriate for a slow dosing over 11 days. If you aren't going on vacation right away, you can try an experiment to see what size opening keeps the FC roughly stable (say, between 1 and 4 ppm). You won't want to use the tub while this is happening and you'll want to make sure that the pump flow doesn't tip over the bottle.

See this thread for how this was done in a swimming pool. Obviously, for your hot tub, you need a far smaller amount of bleach. At 2 ppm FC per day over 11 days in 350 gallons, that would be 2 cups of 6% bleach or 1 quart of half-diluted bleach. A bleach jug is usually 96 ounces (3/4 gallons or 12 cups) so I wouldn't use a full one since you don't want to accidentally overdose. But if you have a spare jug and mix 2 cups of 6% bleach and the rest with water, then this might work.

Richard

That's an awesome idea, thanks. Perhaps a plastic quart milk jug with about a 1/2" hole drilled in the cab would do the trick?

Once again Chem geek, you da man! I'll have to do some experimentation over the next few weeks.

I can't use Bromine, Hot Springs says that I've got this silver coated thingy in my filter that doesn't like Bromine. So, I'm currently using Dichlor. Bleach would be a good fit?

Do yourself the favor of reading more of Richard's posts. Many people are switching to unscented bleach instead of the powdered chlorine products... but you'll still need to keep some dichlor handy. Read this section of the pool and spa forum and to find out why!

The bleach bottle at the bottom of the spa is a good idea... ok it's a genius idea! A quart bottle would be too small and might be more prone to tipping over, so just use an empty 1 gallon bleach bottle. I would say a smaller hole like 1/8" to start testing, then you could increase the chlorine 2X by just drilling another 1/8" hole next to it. Water circ over the top/hole would likely be sufficient to get the small amount of chlorine you're looking for. Remember the goal is for it to last from 1-2 weeks. I'm going to be watching this thread for the results!

[Emprov]

Bleach would be fine. In fact, you should probably be using bleach as your regular chlorine source anyway if you've already been using lots of Dichlor. Dichlor will add to CYA making chlorine less effective so you only need around 1-2 weeks worth of Dichlor after a fresh refill and can then switch to using bleach. For those worried about using a liquid such as bleach that can spill or splash, there's also Lithium hypochlorite powder that quickly dissolves (like Dichlor) but does not add to CYA. It's expensive, though, but for a spa, the quantities are low.

Richard

I've been told that I'd need to drain the tub if I wanted to switch back to Lithium. I liked it when I was using it but I wound up dumping almost a cup of it a day into the tub to maintain the FC. With Dichlor, I'm adding maybe a tablespoon a day and that's about it.

Regarding liquid bleach. How much (ballpark), do you need to maintain the tub at 3ppm? And would you then do a weekly shock with Dichlor? I've read just enough about this stuff from your previous posts to make me irritating to those in the know so forgive the the question if it's repetitive.

Edit: Would putting something in the jug such as lead weights to make sure the jug stays put affect the chemicals at all?

[Emprov]

I'm going to be watching this thread for the results!

Dang, that means that I actually have to get off my butt and do something.

[chem geek]

It is simply not true that you'd need to drain the tub to switch back to Lithium hypochlorite. There is nothing incompatible between the different chlorine sources when in water (though you never mix them in concentrated form). It's possible that initially when you were using it there was no CYA in the water at all so if the tub was exposed to sunlight, then it would break down the chlorine quickly (half gets broken down every half hour at noontime sun) which would explain the heavy usage. Either that or the Free Chlorine (FC) level was measured using a DPD test (intensity of red color; not OTO which is intensity of yellow color or FAS-DPD where you count the titrating drops) which bleaches out above around 10 ppm having one think there isn't a lot of chlorine when there's actually a lot. The Lithium hypochlorite is virtually identical to bleach (in water) so I don't know what was going on with your situation unless it was sunlight. A cup of Lithium hypochlorite is roughly equivalent in chlorine content to 5 ounces of Dichlor which is an awful lot -- I wonder if they really sold you Lithium hypochlorite.

3 fluid ounces of 6% unscented bleach (Clorox Regular or off-brand Ultra) would add 2.9 ppm FC (almost 3 ppm FC) to 350 gallons of water. So if that's the amount of loss per day, then that's how much you'd have to add. A tablespoon of Dichlor would add around 2.1 ppm FC in 350 gallons so that sounds about right.

Richard

[Emprov]

Ok, I'm on vacation and I'm a bit concerned. I played with the bleach a bit and I've yet to maintain a 3ppm FC level in the tub by putting holes in the bleach container. I started off with three 1/8" holes and added a few day after day. Right before I left, I drilled so many holes in the cap that I might as well have left the cap off. BTW, I'm using 4 cups of bleach and filling the rest of the container up with spa water. I shocked and dropped the temp to 85 degrees about a half hour before I walked out of the door so we'll see what it looks like when I get back. In the end, I don't think that the water would have any issues that I wouldn't be able to correct fairly quickly but I'd like to hop into it ASAP.

[chem geek]

I assume you didn't use the tub when you did this experiment with holes in a bleach container, right? Otherwise, there's no way that the slow flow out of the container would be able to keep up with demand from actually using the tub -- adding sweat and having jets running. I also assume that the circulation pump runs at least some time each day even when you aren't using the tub.

As long as there was even some small amount of chlorine in the water, you should be fine. You can just shock the tub with a large dose of chlorine when you get back -- even 5 ppm FC or so and your tub should be quite sanitized very quickly, certainly within an hour (and probably within minutes).

Richard

[Emprov]

I assume you didn't use the tub when you did this experiment with holes in a bleach container, right? Otherwise, there's no way that the slow flow out of the container would be able to keep up with demand from actually using the tub -- adding sweat and having jets running. I also assume that the circulation pump runs at least some time each day even when you aren't using the tub.

We actually only used the tub once in the last week before vaca, life is pretty darn busy so no, we didn't use it. I think that the cap, even though it's completely full of holes, is inhibiting the transfer of bleach into the water. Since the bleach is heavier than water, I'm thinking that not enough is mixing with the water on top to make its way out of the bottle while the cap is on. When I get back, I'll take the cap off for a few days to check it out though.

[Emprov]

We just got back and the first thing that I did after getting home was run out to the spa to check the results. Spa water is pretty cloudy and my test strips showed no hint of FC. So, I know that it needs a shock but I'm dying to get in it tonight, brought it up to between 3-4ppm, adjusted the acid and PH and I'll do the big shock after I use it tonight. Tomorrow, I'll take the cap off of the bleach and try that for a day or so.

[waterboy]

I am wondering if anyone has had any issues with cloudy water etc if they are using a bromine generator such as the Genesis system. Since is should be constantly generating bromine do you just lower the temperature, much sure the water is circulating and enjoy your vacation. We will be receiving our new tub shortly with the Genesis system and we did not consider what needs to be done while on a 3 week vacation.