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Marlig Fix-A-Leak Review – Does It Fix Hot Tub & Pool Leaks?

I bought a used hot tub at my last house, which unfortunately had some leaks. So I looked online and saw Marlig fix-a-leak, and decided to write this Marlig Fix-a-Leak review.

Marlig Fix-a-Leak works due to the fact that the product is heavier than water. Thus, it automatically sinks to the weakest place in the tub which is where the leak is. No need to empty the tub, just remove the filter and pour it in and allow it to work for 24-72 hours before using. 

After I used it, and it worked so well, I wanted to write my own review of Marlig Fix-a-Leak to help others decide if it’s right for them.

If you’re interested, you can see my entire Hot Tub renovation step by step in another post on my site. Just click the link to read it on my site.

What is Fix-a-Leak?

Fix-a-Leak is a pool and hot tub leak stopper made by the company Marlig. It is a liquid that you pour into the filter area of your hot tub (after removing the filters). because Fix-a-Leak is heavier than water, it naturally finds its way to the lowest spot, which is typically where the leak is.

But it is also great for leaks in radiant flooring too.

To be sure, it’s not the only leak stop product on the market. But in my experience with using some of them, Marlig is the best.

It’s a patented formula, so they don’t reveal the exact ingredients.

A typical hot tub will need between 4-8 oz. for fixing a normal leak.

The beauty of it is you don’t have to drain your tub to use it. It hardens and cures underwater in under 48 hours.

After 48 hours, just check for leaks or if the water level has dropped. If all is good, just put the filter(s) back in, adjust the water chemistry as needed and you’re done.

How long does Fix-a-Leak last?

Fix-a-Leak permanently seals small holes and cracks, and most leaks are fixed within 24-48 hours. Fix-a-Leak seals leaks as large as 1/8″ around. So Fix-a-Leak is for holes that are up to 1/6 the size of a dime.

So this is not going to fix some giant crack in a PVC pipe. 

I’ve had leaks in my hot tub where a PVC pipe had a large crack. I’ve also had worn out rubber gaskets that had cracked. 

Fix-a-Leak can slow those leaks for a time but isn’t likely to stop them fully.

But for small leaks where the jets are fitted to the tub, loose fittings of pipe inside the insulated foam, Fix-a-Leak is going to work great. In my experience using it, once it’s fixed, it stays fixed.

I’ve never had a situation where a previously fixed leak starts leaking again much later.  You’ll know within 48 hours if it stopped your leak. If it did, the chances are very high that it will stay that way.

The only thing I will say is we are dealing with heat which can lead to expansion and contraction.

And we also have the vibration of the equipment and users. All of those things could lead to leaks re-occurring later, but I have not experienced that personally.

Luckily, Fix-a-Leak is pretty cheap and since you often don’t need more than 8 oz. at a time, it’s not hard to re-apply every year or so.

Curious about Marlig Fix-A-Leak? Just click the link to see the current price on Amazon.

Why is my hot tub leaking from the bottom?

When a hot tub leaks from the bottom, the most likely cause are worn gaskets in the union fittings on either side of the heater tube. But cracks in the PVC pipes are also possible.

One night while soaking, my wife and I heard a loud crack while we were in the tub. We looked but could see no visible evidence of any issues.

However, within a few days, I began to notice the tub was losing about an inch of water per day. I also noticed excess moisture on the paver stones the tub sits on.

Not good!

I pulled some of the sides off the hot tub and saw at least 4 leaks, including my hot tub leaking from the bottom. Unfortunately, 3 of the leaks were encased in that spray insulation foam that is typical of hot tub undersides.

I wasn’t sure what to do and was worried my time and money invested in rebuilding the hot tub might have been wasted.

I frantically searched the web for a hot tub leak sealer and came across Marlig Fix-A-Leak on Amazon (click to check it out and read more reviews).

The reviews admittedly weren’t mind-blowing. But then most of the hot tub stop leak products on Amazon had under 4 start reviews.

3 1/2 stars was the total for Marlig Fix-a-Leak.

Lots of great reviews, but enough bad and mediocre ones to make me question if it was a good investment. It also isn’t the only hot tub leak sealer on Amazon.

Does Fix a Leak work?

Marlig Fix-a-Leak works exceptionally well on permanently fixing small cracks in the plumbing of the hot tub. It will not, however, fix large cracks or holes in the acrylic shell of the hot tub.

After reading the reviews, I bit the bullet and purchased a quart-sized bottle of Marlig Fix-A-Leak (click the link to see the current price on Amazon).

I read the directions carefully.

Next, I removed the filter from my hot tub. Then I turned the filter settings to on (so that it sucks water through the system). The instructions said to pour the Marlig Fix-A-Leak near the leak or near the intake if you aren’t sure. ‘

I just poured the hot tub leak sealer down the hole where the filter normally sits.

Luckily, I only used about a 3rd of the quart-sized bottle since that was what it recommended. So I had plenty left over for future uses. I had also previously filled the tub right up to the lip so I could easily tell if it continued to lose water.

The next day, I went out and cautiously lifted the lid, expecting to see a big drop in water level.  Amazingly the level was exactly the same.  I also saw no moisture on the pavers that my tub sits on.

How can I tell if my hot tub is leaking?

The easiest way to tell if your hot tub is leaking is you will either see water on the ground around the base of it. Or you will notice unusually large drops in the water level in the tub.

In my case, on the 3rd day of zero change in water level, I put the filter back in and applied my normal water treatments. By the 4th day, we were back in the tub as usual!  So far that was about 3 months ago and we’ve experienced no issues.

Even if I have to repeat this process a couple of times a year, since I only used 1/3 of the Marlig Fix-A-Leak, I could easily repeat the process 2 more times before needing to buy another bottle.

Even with purchasing 10 bottles of hot tub leak sealer, that’s still less than having a repair person come out to fix your leaks.

So in my experience and in my Marlig Fix-A-Leak review, I think this product works perfectly and did exactly what it says it does.

Want to check my story out? 

You can actually see my Marlig Fix-A-Leak review on Amazon’s product page. It’s under my wife’s name since our Prime account is under her name; Cassandra Campbell.  You’ll also see it’s a verified purchase. 

Thus my Marlig Fix-A-Leak review is truly the accurate story of my purchase and use of their hot tub leak sealer.

Want to buy it?

You can purchase Marlig Fix-A-Leak (click to buy on Amazon) right now through my affiliate link. 

An affiliate link doesn’t cost you anything extra; Amazon just pays me a small percentage for sending you to them. And with your Amazon Prime account, you can have your hot tub, spa or pool back up in just a matter of days!

How does Marlig Fix-A-Leak work?

Marlig Fix-A-Leak is a blended concentrated liquid. It’s designed to seal leaks in almost any material. 

It can be applied to leaks in the shell but also works great with leaks in the plumbing systems of pools or hot tubs. Amazingly, it will seal holes 1/8″ in diameter and forms a permanent seal.

Use 1 quart per pool up to 22,000 gallons, but a max of 1 quart per 5,000 gallons of water. For my hot tub, I literally just used about a 3rd of a bottle, and I probably could have used less.

Note the water level at the time you start to fix your leak.

First, remove the filter. Then while the pump is running, add Marlig Fix-A-Leak slowly through the skimmer or anywhere that the water is sucked into the plumbing system.

Marlig Fix-A-Leak is heavier than water, so it sinks to the lowest point in the pool or spa quickly. Typically the lowest point will be where the leak is. 

In a pool, for best results, manually stir with a pool broom or with an automated pool cleaner such as a Polaris, about every 4-6 hrs. In a hot tub, just ensure the pump and heater stay on and circulate their normal cycle.

Continue to recirculate water until the leak has stopped. After 2-3 days, check the water level and see if the leak has stopped.

Once the leak has stopped, allow it to cure an additional 48 hours, replace the filter, treat the water as needed, and resume normal use.

Do hot tubs lose water?

All hot tubs lose some water naturally due to evaporation.

How much water gets evaporated is based on:

  • How humid your weather
  • The temp you set the hot tub to
  • How often you use it
  • The frequency the lid is left open

All that being said, under maximum conditions, you might see 1-2 inches per week lost.

But there’s much more that goes into hot tub water loss, how to tell if it’s evaporation or a leak, winterizing your hot tub, and more.

So, make sure and check out my post that goes deep into Do Hot Tubs Lose Water? (just click to read it on my site).

How much does it cost to fix a hot tub leak?

Most hot tub leaks can be fixed for under $50. But it may require trying a few different approaches to locate and seal the leak, including using Fix-a-Leak, patching larger cracks with a waterproof epoxy, or replacing worn rubber gaskets. A professional may charge $400 or more to locate and fix the leak.

If you try Marlig Fix-a-Leak and it just won’t stop your leak, most likely you have a cracked pipe or fitting somewhere under the tub.

In my case, while that wasn’t true when I first wrote this article, it did happen about a year later. So I wanted to come back and add to my post to talk about this process.

First off, if you are handy at all, see if you can fix it yourself. 

Repair people will charge you a minimum of $200 to fix a hot tub leak, and it could go well over $1,000 depending on where the leak is if they have to remove the spray foam insulation to get to the leak, etc.

In some cases, the repair cost from a spa repair company might not even be worth it for what you could buy a new one for.

In my case, I pulled the siding off my hot tub and saw the connector between the heater and the pump was leaking badly due to a crack.

I simply closed the valves on either side of it to cut the water off (but you could simply drain yours if you don’t have those).

Then I pulled the pipe that was cracked off the end of the pump. Because it was a large pipe that ran well into the hot tub, I knew it wouldn’t be easy to replace. 

So I bought what’s called a patch-clamp or pipe clamp.

These just slide over one end of the pipe. Then you reconnect the cracked section and slide the pipe clamp directly over the crack and tighten it down. It basically just tightens and grips where the crack is to keep it from leaking.

In my case, that worked perfectly and I was able to fix my larger hot tub leak for under $20 with about an hour of my time.

Final Thoughts

In this review, I covered the exact problems I had with my hot tub leaking.

Specifically, I went over exactly how I used Marlig Fix-a-Leak to correct the problem quickly & easily.

Whether your hot tub leaking from the bottom, a crack in the acrylic, or one of the jets, I bet you’ll find that Marlig Fix-a-Leak hot tub leak sealer will work for you, just like it did for me.

CLICK HERE to check out Marlig Fix-a-Leak on Amazon.

If you buy it and try it, I’d love to hear how it worked for you. So feel free to comment here.

Jeff Campbell