New hot tub owner & maintainer, 180 gallon inflatable

[wilde]

I've lived in Colorado for 4 years and got the wild hot tub hair for the star filled sky and yard.  We're only gonna use it every other weekend and then treat and drain for a couple of weeks until next fill and reheat.  There may be 3 to 4 soaking hours of use each refill, or 1 hour a day average over the weekends it's used.

It has two paper filters and is a SaluSpa Realtree MAX-5 AirJet 4-Person Portable Inflatable Hot Tub Spa. 

I know ZERO about safe spa water so please tell me if this will do for upkeep if the water smells and looks OK when it's filled and used:

1. I've used it for first time this past weekend.  I filled it Friday 4pm with 180 gallons of softened well water and put 2 fluid ounces of 8.25% liquid household bleach into it and let it heat up to 104 degrees F.  This took 24 hours to heat up.

I looked and smelled the water Saturday night 9pm and it seemed fine, maybe a slight hint of chlorine...either that or the new plastic smell from the tub construction.  3 people got in it for 45 minutes.  I put the cover back on and then Sunday at 7pm I put another 2 fluid ounces of 8.25% chlorine bleach and used it again for 1 hour at 9pm, allowing it to breath for 15 minutes with the cover off before getting in.

When finished I put the top on, turned the heat off, put 1 cup (8 fluid ounces) of 8.25% bleach into it and let it circulate until next morning.  I then drained the tub and pump/heater unit and let it dry as best I could in the dry Colorado shade. I rinsed and dried the paper filter elements that still looked very clean.

2.  Will this treatment plan be okay ya think, as long as the water looks and smells clean or neutral?  Do I need a testing kit for anything?  I want to keep this as low maintenance as possible so I don't get tired of it.

3.  Am I using too much or not enough 8.25% chlorine?  I'm using slightly more (it says 1 teaspoon per 8 gallons drinking water) than the amount the EPA and CDC webpages say to use to make drinking water safe.  I figured if it makes it drinkable it may be enough for my use type.

If you can tell me the best and easiest way to tend to this little tub, used occasionally, I'd appreciate it a lot!  For supplies, I have a Walmart nearby, and am an Amazon user also.

Thank you!  Andy

 

 

 

 

 

[MPurcell]

Spa water should be balanced as well as sanitized. pH should be in the range of 7.2 to 7.8. 7.0 and 8.0 are usually considered the outside limits. You should first find out if your fill water falls in the recommended pH range. (My well water is about 6.8 pH and naturally soft, but I am in Georgia which is likely much different than Colorado.) With your plan, pH is the only balance issue I would be concerned with.

For chlorine, you can use the Pool Calculator to determine the correct amount. For instance, 2 oz of 8.25% bleach will raise the chlorine level of 180 gallons from 0 to 7.4 ppm.

The problem you will have with chlorine and no test kit is keeping the level up high enough to be safe, and at the same time not so high it is harsh. With no stabilizer in the water, the chlorine will dissipate quite rapidly from the UV component of sunlight. The high heat will also cause the chlorine to outgas and dissipate. Bather load will use the chlorine up rather quickly as well. If you allow the chlorine level to go down to 0, even for a few hours, you could have an unsafe condition in the water with bacteria. The best plan would be to add chlorine immediately after each period of soaking, enough to neutralize bather waste plus a little to keep the level up. Bather waste depends on temperature and time in the water. 1 person for 1 hour at 104 degrees uses the chlorine equivalent of about 3.5 oz of 8.25% bleach.

The biggest problem you might have would be the buildup of bio film in the plumbing. It will be difficult, if not impossible to get the plumbing completely dry after emptying, so bio film can continue to build up between fills. Super-chlorinating before draining will not be enough to reduce the bio film, which is resistant. You should probably do some reading about the issue if you are not aware of it. The best product available to clean the plumbing is Ahh-some, which is a little pricey but can be used before draining.

[wilde]

OK thank you.  I ordered a 5-way Poolmaster test kit for $18 on Amazon.  Is this a good value?

My wife hates chlorine and chemicals and wants me to figure out how to use the minimum amount of it during the short 4-day use cycles we'll use it.  She also wants to have Epsom Salts in the water to help her muscles and skin.  She hates the way pool chemicals smell and make her skin feel.

I'm thinking that maybe I want to sanitize the enclosed pump system by adding a short return and supply tube from a 5 gallon bucket to the pump/heater system.  I'll "shock" the 5 gallon bucket with 8 fl oz 8.25% bleach and run the pump/heater for 15 minutes, let it sit still for 15 minutes, flush for 5 minutes with fresh water, and then put it in use for its 4-day use cycle.

So my clean, fill and use cycle will be like this:  

1. Shock treat/flush the portable pump/heater system with 8 fl oz 8.25% chlorine in 5 gallon bucket for 30 minutes. Rinse for 5 minutes with fresh water.

2. Fill cleaned/sanitized tub with 180 gallons fresh water and add 2 fl oz 8.25% chlorine bleach to keep clean as it warms for 24 hours. Test water about 12 to 18 hours during heat up process.  Add 1 fl oz chlorine as-needed.

3. After 24 hours but at least 2 hours before use do water tests.  If okay, add 10 cups of Epsom salt to tub and wait 1 hour.  Test again.

4. If test okay, begin use for the 3-day soaking cycle.  If not okay, add chlorine as-needed to make it good.

5. Test 1 hour after each soak and add 1 to 2 fl oz 8.25% bleach as-needed and retest an hour later.

6. After day 4 I'll shock the pool water and pump/heating system with 8 fl oz 8.25% chlorine for an hour, drain water, dry pool/pump components and store with lid on until next use.  Oh, and of course clean and dry the filters.

I'm hoping that with our light and clean use (maybe 3-4 soaking hours per 4-day water cycle) that the Epsom Salts and chlorine will be sufficient to keep the pool chemistry sanitized and within balance.

I don't think chlorine and magnesium sulfate react adversely but I'll read up on that.

Has anyone good experience with anything similar, or read another forum users post that has made this short use cycle with fresh water mixed with Epsom Salt work with good water quality, with minimum additions of chemicals?

 

[MPurcell]

That test kit is certainly better than having no test kit. It is also better than test strips. The pH test should be fairly reliable. Since your are only keeping the water for three or four days, you will not need to test for total alkalinity. The main thing is keeping the pH in range. The chlorine test is based on orthotolidine, which is the least reliable of the drop tests for chlorine, as far as getting an accurate ppm of chlorine. But it is perfectly reliable as a test for the presence of chlorine. If you get any yellow color at all in the sample, then chlorine is present. If chlorine goes to 0, then the sample will remain clear. You can get a general idea of how much chlorine is present, but the color matching is difficult for some. A very good value, even if it is a little bit limited. A proper taylor test kit for chlorine would run you $60 to $100, but that would be overkill in your situation.

Epsom salt should not be a problem. It will add magnesium hardness to the water which will reduce foaming similarly to calcium hardness. The presence of magnesium may cause the heater elements to deteriorate a little faster, but not sure if this is significant. I wouldn't use much more than about a pound of epsom salt for 180 gallons.

Keep the free chlorine no lower than 1 or 2 ppm at all times. In a hot tub, low or no chlorine can result in a very rapid buildup of bacteria. Free chlorine really has very little smell and should not be irritating. When the chlorine interacts with bather wastes, it forms combined chlorine, and then the combined chlorine is oxidized by additional chlorine. It is the combined chlorine that causes the unpleasant smell that makes some commercial swimming pools so unpleasant. So just be sure to use enough chlorine to burn off the bather waste completely, and your wife should not be adversely affected.

I'm serious about the bio film. Just read this.

If you need to adjust pH higher, you can use regular baking soda from the grocery. If you need to adjust pH lower, you will need either dry acid or muriatic acid, which you will need to get from a pool/spa store or online supplier. You can use the pool calculator to determine how much to use.

[wilde]

Can I use white vinegar (5%) to lower Ph?  For such a small tub 180 gallons.

[MPurcell]

No. It's not nearly acidic enough, and the organic component would be undesirable. First wait till you know if you even need to lower pH. Then if you do, just get some dry acid. With well water, my guess that you will need to raise pH if anything.

[MPurcell]

One thing I'd like to add to the equation. Heat dissipates chlorine. This is usually not much of an issue in a swimming pool or a chlorine spa, because there is also cyanuric acid (CYA) stabilizer in the water, and approximately 95% of the chlorine is bound to the stabilizer. In your situation, however, since you are using bleach, there is no stabilizer at all. Chlorine consumption doubles for each 13 deg F increase of temperature, so even with the cover on, a tub at 104 deg F will dissipate 4 times as much chlorine per day as a tub at 78 deg F, and 8 times as much chlorine as a tub at 65 deg F. You should take this into consideration when adding chlorine. The instability of chlorine with heat is one reason that hot tubs often use bromine. Chlorine in a hot tub with about 40 ppm of CYA is relatively temperature stable compared to one with no CYA.