There are many reasons behind needing to know the measurement of gallons of water your hot tub can hold. Some purposes for this information include adding the right amount of cleaning chemicals, estimating your water bill, or calculating if your patio will support your tub’s weight.
The number of gallons of water in a hot tub is dependable on size and shape. Some of the smallest two-person hot tubs can hold 150 gallons of water or more.
Read on to find out how to determine how many gallons of water your hot tub can contain, why it’s essential to know how many gallons of water your hot tub can hold, as well as some tips on upkeeping your tub to ensure proper and safe usage.
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The Amount of Water in Different Sizes of Hot Tubs
Depending on if your hot tub is rectangular or circular shaped and the size measured by how many people can fit inside, there is a difference in the amount of water it can hold. The weight of your hot tub when filled with so many gallons of water can also get quite hefty, so it’s best to get one that weighs under 3,000 pounds when filled to avoid breaking through your patio.
Two-Person Hot Tubs
Most two-person hot tubs hold a range from 150 to 220 gallons of water. Typically, these hot tubs weigh about 2,576 pounds when filled with water. This hot tub size will be ideal for you if you plan to put it on a patio, as most decks can only hold up to 3,000 pounds.
Three to Four-Person Hot Tubs
Hot tubs that fit three to four people can hold anywhere from 200 to 300 gallons of water. They generally weigh about 3,185 to 3,700 pounds when filled with water.
Hot Tubs That Fit Five Or More People
Hot tubs that can fit five or more people can hold a range of 32 to 475 gallons of water, and more. These large tubs can weigh anywhere from 3,700 to 4,300 pounds and up.
How to Evaluate How Many Gallons of Water Your Hot Tub Can Hold
There are tons of methods to find out how many gallons of water are in your hot tub. Some of these methods are simpler, and some take a lot more work, but the effort is worth it.
Read Your Hot Tub’s Manual
Your hot tub’s manual is a guide to anything and everything about the tub. Flip through it, and you can find the number of gallons of water that your hot tub can hold. If you don’t have the manual for your hot tub, try using another method.
Call the Establishment You Bought Your Hot Tub From
The person who sold you your hot tub should know the dimensions and water capacity if they still hold the specific make and model. Give them a call and ask a worker, but if they don’t know or you bought your hot tub secondhand, another method might work for you.
Consult with The Manufacturer
Your hot tub should have the manufacturer’s name somewhere on it. If you do a quick search on the company’s name, you may be able to find their business website or their contact information. Send an email or call them, and they should be able to guide you. If your hot tub manufacturer is out of business, you might have to use a different method.
Search the Internet
There should be a label located somewhere on your hot tub that states its serial or model number. You can use this number to search for how many gallons the tub can hold, and some information related to your hot tub or its manual should also show up.
Record the Time It Takes Filling Your Hot Tub
Using a five-gallon bucket and a stopwatch, you can determine how many gallons your hot tub holds using basic math. Time how long your hose takes to fill up the bucket, and document this data in minutes and seconds. Then use the following steps:
- Time filling your hot tub in minutes and seconds.
- Multiply the minutes it took by sixty and add the remaining seconds. Separately do the same for the time it took to fill up the bucket. The numbers you get from doing this is the total time in seconds of filling both bodies with water.
- Divide the time, in seconds, it took to fill the hot tub by the time it took to fill the five-gallon bucket.
- Multiply the number you got by five to determine the number of gallons of water your hot tub can hold.
Manually Measure Your Hot Tub
If all else fails, manually measuring your hot tub is the best way to calculate precisely how many gallons of water your hot tub can hold using simple math. However, there is a difference between measuring a rectangular-shaped hot tub and a circular-shaped hot tub.
With rectangular tubs, use a measuring tape to find the length, width, and depth in inches. Multiply the width by length by depth, then divide the answer by 1728. If the tub has seats, take the number you got and multiply it by 2.4; if it doesn’t, multiply the number by 4.8. Your final number is the gallons of water your hot tub can hold.
With circular tubs, use a measuring tape and determine the length across the tub’s center, then the depth in inches. Multiply the diameter by the depth and divide the number you get by 1728. Whether your tub has seats or not, you multiply the number by 2.4 or 4.8 like a rectangular-shaped tub for the same result.
The Cost of Running A Hot Tub
The thing about maintaining your hot tub is, it involves a lot of fluctuating water consumption. Every time you have to drain and refill your hot tub, your water bill will rise based on the number of gallons of water you use to fill it up. Knowing the number of gallons your hot tub can hold can give you an estimate for that month’s water bill.
Depending on your water bill’s cost, some factors in the equation to determine your estimate will be different, but the setup is solid. To find the additional fee to your water bill from filling your hot tub, multiply the capacity in gallons of water it holds by your cost for water by 0.00134.
For example, if I own a hot tub that holds 475 gallons of water, and my water bill costs $12.08, I would multiply these by 0.00134 to get 7.68892. This number would round up to 7.69, meaning my water bill will be $7.69 more the month I refill my hot tub.
Maintaining Your Hot Tub
It is essential to keep your hot tub clean with chemical solutions like chlorine and stay on top of draining and cleaning it to ensure safe usage. Knowing the number of gallons in your hot tub is vital to complete these tasks when needed.
Sanitizing Your Hot Tub
Chlorine is needed to kill bacteria from people like:
- Skin cells
So, your hot tub can stay safe to soak in. Most chlorine brands say you should put two teaspoons of the product per 200 gallons of water in your tub. However, it would help if you still used test strips to ensure there isn’t too much or too little of the chemical in your tub. If you’re not wanting to use chlorine, be sure to check out our article were we provide different alternatives to help keep your hot tub sanitized.
Draining Your Hot Tub
You should completely drain and clean your hot tub every three to four months to flush out any remaining unwanted bacteria that chlorine cannot fully break down. You can do this by using your hot tub’s spigot or using a submersible pump. Always make sure to turn your tub’s power off before commencing with draining. If you have a pool, you can also use that to drain your hot tub water.
When draining using your hot tub’s spigot, attach a hose to it and lead it downhill to an area where your yard will not be damaged by the water which will flow out. Then, open the ball valve so your hot tub’s water can start draining. There may be another spigot for the internal bleed lines, which you should also drain.
When draining your hot tub using a submersible pump, place the pump into the hot tub and lead its hose as you would when draining with a spigot. Next, turn the pump on and let it drain.
After draining your hot tub entirely, you should clean the shell with a clean damp rag and a cleaner that is safe to use, according to the manual. The last step to maintaining your hot tub is to clean the filter, and then you can refill your hot tub and enjoy soaking again.
The number of gallons of water in a hot tub depends on the size and shape of the tubs because every hot tub is made differently. If you need to know the number of gallons of water your hot tub can hold for any reason, the different methods listed here make it no hassle.