Setting up your inflatable hot tub for the very first time is genuinely exciting but it’s also the stage where most beginners make avoidable mistakes. Fill it too little and the jets underperform. Fill it too much and water spills every time someone climbs in. Skip the chemical step and you’re soaking in unbalanced water within days.
At Relxtime, we want your first fill to go smoothly from start to finish. This complete hot tub first time filling guide walks you through every step from positioning and inflation right through to the moment you can safely slide in and relax. Whether you’re setting up in summer or tackling the challenge of filling a hot tub in the winter, this guide has you covered.
Before You Fill Essential Preparation Steps
Rushing straight to the garden hose is the number one beginner mistake. A little preparation before the water goes in saves hours of frustration later.
Choose and Prepare Your Location
Before a single drop of water enters your tub, confirm your placement is solid. Your filled Relxtime inflatable hot tub will weigh between 800 kg and 1,200 kg a flat, hard, load-bearing surface is non-negotiable.
- Place your insulated ground mat on a level concrete, paving slab, or compacted surface
- Confirm there is no slope greater than 1–2 degrees
- Ensure you are within safe reach of a weatherproof GFCI electrical outlet
- Check that your drainage path is clear for when you eventually empty the tub
Inflate the Hot Tub Correctly
Inflate your tub using the included pump before any water is added. This is much easier on a dry, flat surface. Follow these checks:
- Inflate to the manufacturer’s recommended pressure usually marked on the tub or in the manual
- Check all air valves are fully closed and sealed after inflation
- Run your hand around the seams and walls to feel for any slow leaks
- Let the tub sit inflated for 10–15 minutes before filling to confirm it holds pressure
Install the Filter Cartridge
This step is consistently overlooked by first-time owners. The filter cartridge must be installed before you begin filling. Trying to install it once the tub is full is awkward, messy, and risks contaminating the water. Check your Relxtime manual for the correct cartridge orientation and ensure the housing cap is firmly tightened.
How to Fill an Inflatable Hot Tub Step by Step?
With preparation complete, you’re ready to fill. Here is the full step by step hot tub setup water-filling process.
Attach Your Garden Hose
Use a standard garden hose connected to your outdoor tap. For most Canadian homes, the outdoor tap water supply is perfectly suitable for hot tub filling. A few tips:
- Use a hose that reaches comfortably without being stretched tight
- Avoid using a pressure washer attachment too forceful
- If your outdoor tap has been off for winter, run it briefly first to flush any stale water from the line
Direct Water Through the Filter Housing
This is important and often missed in generic guides. Rather than simply dropping the hose into the tub, direct the water through the filter housing inlet. This pre-filters the incoming water and prevents air locks in the filtration system. Check your Relxtime setup guide for the correct inlet point on your specific model.
Fill to the Correct Water Level
How full should you fill a hot tub? The water level should sit between the minimum and maximum fill markers on the inside wall of your inflatable spa typically around the middle point of the interior wall height.
| Fill Level | What It Means |
|---|---|
| Below minimum line | Jets won’t function properly; pump may run dry |
| At minimum line | Acceptable but limited comfort for multiple users |
| Between min and max | Ideal jets perform fully, safe water displacement |
| Above maximum line | Water overflows when users enter; potential pump damage |
As a general rule, how much water does an inflatable hot tub need is roughly 800–1,000 litres for a standard 4-person model. Your specific Relxtime model’s capacity will be listed in the product manual.
Monitor the Fill the Entire Time
Never walk away and leave the tub filling unattended. Water fills faster than most people expect, and overfilling even briefly can stress the seams and cause unnecessary water waste. Stay nearby and check the level every few minutes as you approach the maximum line.
Turn Off and Disconnect the Hose
Once you reach the correct fill level, turn off the tap and disconnect the hose fully. Check the filter housing cap is secure one more time, then move on to the chemical stage.
How Long Does It Take to Fill an Inflatable Hot Tub?
This is one of the most common questions from first-time owners, and the honest answer is it varies.
| Factor | Impact on Fill Time |
|---|---|
| Tub size (litres) | Larger tub = longer fill time |
| Water pressure | Higher pressure = faster fill |
| Hose diameter | Wider hose = faster flow |
| Average fill time | 45 minutes to 2 hours |
Most standard inflatable hot tubs take between 1 and 1.5 hours to fill with a regular garden hose at normal Canadian household water pressure. Budget 2 hours to be safe, especially on your first fill.
How Long After You Fill a Hot Tub Can You Use It?
This is where patience pays off. Once the tub is filled, you cannot use it immediately. Here’s why and here’s the timeline:
The First-Use Waiting Timeline
Step 1 Heat the water (2–24 hours) Your tub needs to reach a safe soaking temperature of 37°C–40°C. Starting from cold Canadian tap water (often as low as 10°C–15°C), this can take anywhere from 12 to 24 hours depending on your model’s heater wattage and the outdoor temperature.
Step 2 Add and balance chemicals (30–60 minutes after heating) Once the water is warm, add your sanitiser (chlorine or bromine) and pH balancer. Allow at least 30–60 minutes for chemicals to fully circulate and stabilise before entering.
Step 3 Test the water Use a test strip to confirm:
- pH level: 7.2–7.6
- Sanitiser level: 3–5 ppm (chlorine) or 3–5 ppm (bromine)
- Alkalinity: 80–120 ppm
Once all readings are within range, your tub is ready to use. Total wait time from filling to first soak: typically 12–26 hours.
Filling an Inflatable Hot Tub in Winter in Canada
Winter filling adds extra steps but is absolutely doable. Here’s your hot tub setup water instructions adapted for cold Canadian conditions.
Tips for Filling Up a Hot Tub in Winter
Use warm water if possible If you can run a hose from an indoor hot water tap, starting with warmer water dramatically cuts your heat-up time. Some Canadians use a combination of cold outdoor hose and warm water from an indoor source via a long kitchen or utility hose.
Pre-warm the tub shell An inflatable hot tub sitting in sub-zero temperatures will be very cold to the touch. Inflate the tub and allow it to sit in a sheltered location for an hour before filling this reduces the thermal shock on the PVC material.
Fill faster, not slower In freezing temperatures, a slow fill risks the water starting to cool or even freeze near the base before you reach fill level. Fill at maximum tap pressure and work efficiently.
Cover immediately after filling The moment you stop filling, place the insulated cover on the tub. Every minute of uncovered water in winter means lost heat and longer wait times.
Protect your hose Drain the garden hose completely after filling and bring it indoors leaving water in an outdoor hose overnight in Canadian winter risks cracking and damage.
Water Filling Tips for Inflatable Hot Tubs Quick Reference
Here’s a summary checklist for your first time hot tub setup water instructions:
- ✅ Inflate and check for leaks before filling
- ✅ Install filter cartridge before any water goes in
- ✅ Fill via the filter housing inlet, not directly into the tub
- ✅ Fill to between the minimum and maximum water lines
- ✅ Never leave the tub unattended while filling
- ✅ Allow 12–24 hours for water to heat fully
- ✅ Balance chemicals before first use
- ✅ Test water with strips before entering
- ✅ In winter cover immediately after filling and drain the hose
Common First-Time Filling Mistakes to Avoid
Even with a guide, a few mistakes are remarkably common among beginner hot tub owners. Watch out for these:
Skipping the filter cartridge installation running the pump without a filter ruins the cartridge housing and contaminates your water immediately.
Filling too fast without watching the level overfilling strains seams and wastes water. Stay present.
Getting in too soon unbalanced, unheated water is uncomfortable at best and unsafe at worst. Wait for the full heat-up and chemical balance cycle.
Not checking pH before the first soak tap water pH varies across Canada. Never assume it’s balanced always test.
Conclusion
Filling your Relxtime inflatable hot tub for the first time doesn’t have to be complicated but it does require doing things in the right order. Prepare your surface, inflate correctly, install the filter, fill to the right level, heat the water fully, balance your chemicals, and test before you soak. Follow this inflatable hot tub setup and water filling guide and your first session will be everything you hoped for.
Whether you’re setting up in a warm Canadian summer or braving a winter fill, taking these steps seriously means a cleaner, safer, and more enjoyable hot tub from day one. Your backyard retreat is closer than you think.
Frequently Asked Questions?
Here are some frequently asked questions given below:
How full should I fill my inflatable hot tub?
Fill your inflatable hot tub to between the minimum and maximum fill lines marked on the interior wall typically around the mid-point of the inner wall height. Underfilling reduces jet performance while overfilling causes water displacement and potential pump strain when users enter.
How long does it take to fill an inflatable hot tub?
Most standard inflatable hot tubs take between 1 and 1.5 hours to fill using a regular garden hose at normal household water pressure. Larger models may take closer to 2 hours. After filling, allow a further 12–24 hours for the water to heat to soaking temperature.
How long after filling a hot tub can you use it?
You should wait until the water has fully heated to your target temperature (37°C–40°C) and your chemical levels have been balanced and tested. This typically takes 12–26 hours from the point of filling. Never enter a hot tub with untested or unbalanced water.
Can I fill my inflatable hot tub in winter in Canada?
Yes, with the right approach. Use warm water where possible, fill quickly to prevent heat loss, cover the tub immediately after filling, and drain your garden hose indoors afterward to prevent freezing. Your Relxtime model’s heater will take longer to reach temperature in cold weather, so plan for a longer heat-up time of up to 24 hours.
Do I need to add chemicals the first time I fill my hot tub?
Absolutely. Even fresh tap water needs to be chemically balanced before use. Add your sanitiser (chlorine or bromine) and pH balancer once the water has heated, allow 30–60 minutes for circulation, then test with strips to confirm safe levels before your first soak.
