Underwater Drones: Gladius Mini VS FIFISH V6 – Full Comparison

Gladius Mini vs FIFISH V6 - Best Underwater Drone - featued Image

Table of Contents

2019 is going to be a great year for underwater drones. And this year it seems that the focus will be on two new underwater drones, the Gladius Mini and the FIFISH V6. These 2 amazing underwater drones bring us a new set of expectations while keeping a truly affordable price tag. And since you are not planning to buy them both, I decided to check them out and see which one is better than the other. So, let’s dive in and check the Gladius Mini vs FIFISH V6 underwater drones.

Gladius Mini VS FIFISH V6 – The Surprises on Both Drones

Before we begin with the comparison, I want to point a few features that are new to the underwater drones, however, both underwater drones have them.

HDMI Output

Before I will start with the Gladius Mini vs FIFISH V6 comparison, I would like to point out a great new feature that both drones have, which is the HDMI output.

Having an HDMI output for your underwater drone means you can sit in your boat or yacht and connect it to a computer monitor, plasma screen or even a TV, and by that, you can see clearly what’s going on under the water. This is a huge improvement since, you can stop seeing thru the small screen of your phone, tablet or iPad.

Depth Lock

The depth lock is yet another great feature in both the Gladius Mini and the FIFISH V6. The name stands by itself, meaning once you set the depth you want, the drone will keep that depth level, and you can now move it forward, backward, left and right and the drone will keep its depth. This is great for supervision or filming.

Tilt Lock

One of the cons of underwater drones is the fact that most of them cannot tilt. Tilting is very essential when you need to inspect or follow objects on a grainy ground, like sand. Since the thrusters will bland the sand, it will result in an unclear image in front of the camera.

For example, if your mission is to follow a fish on the ground, that will be almost impossible. And if you need to search for something on the ground, your only way to do it will be by landing the drone on the ground and not move the drone so the thrusters won’t blend the sand. It is possible, but no one will have the patience to do it this way.

Here is a short video of the FIFISH P3 while trying to inspect an object on the ground:

So, by having a tilt lock, inspecting objects, or even following objects on the ground is now easy.

Keep in your mind that even with the tilt lock feature the sand will blend on the ground, so, it all depends on how powerful you set the thrusters on.

In this manner, the FIFISH V6 has even more capabilities than the Gladius Mini, but I will get into that in a moment.

Gladius Mini VS FIFISH V6 – Let’s Begin

Like I did on other comparisons, like for best fishing drones or fishing camera, I will explain what I am about to compare between the Gladius Mini and the FIFISH V6.

We will first compare the content that comes with the drones, available accessories, features, some specs for each one, and finally the price.

Gladius Mini VS FIFISH V6 – Package Content

Gladius Mini vs FIFISH V6 - package content - small

The basic package of the Gladius Mini comes with a base station, remote controller, reel with 50 meters of tether one charger, which can charge both the drone and the base station and 2 buoyancy weight models – one for saltwater and one for freshwater.

The base unit of the Gladius Mini is a WiFi module which allows you to control the Gladius Mini using a wireless remote controller. Another great thing about the base unit is the fact that there is a slot for a microSD card. Basically, it is allowing you to store the footage directly on the base unit and not on the drone.

However, regarding the wireless feature, you need to be aware of a few risks about it. First, the base unit is not waterproof, so make sure you place it is a safe place. Second, since your eyes are going to be on the monitor and not on the base unit, if you will send the drone longer than 50 meters (or whatever length you chose), you will say goodbye to your base unit and to the drone as well. Last, let’s say you sent the Gladius Mini only 20 meters, which leaves you with another 30 meters, however, there was something in the tether that got stock like a knot (or something alike) that will pull your base unit towards the water as well. So, please make sure you secure the base unit before using the drone.

As for the FIFISH V6, it comes with 50 meters of tether, a remote controller and 2 chargers for both the drone and the remote controller. However, it does not come with a spool and an HDMI module, which in case you are interested in, you will need to purchase that separately.

Gladius Mini LogoFIFISH V6 logo
ProsAn HDMI Output comes with the basic package.Separated chargers for the drone and the remote controller.
A Winder comes with the basic package.The FIFISH V6 has a handle to lift it up out of the water.
The tether has a special loop that goes around the back tail, which reduce the pressure when pulling the drone out of the water.
ConsThe Base unit is wireless which except for being wireless it is too risky and you can lose your drone easily.There is no HDMI unit in the basic package – it can be purchased separately.
The base unit is not waterproof.There is no winder in the basic package – it can be purchased separately.
The package comes with only one charger – I don’t see an option to buy another one separately.

Gladius Mini VS FIFISH V6 – Additional Accessories

Gladius Mini vs FIFISH V6 - accessories - small

A very important thing when buying a drone is the offered accessories it can have. When dealing with underwater drones, there aren’t too many accessories, however, some of them are very essential for your adventure to be successful.

For the Gladius Mini, there are currently 2 additional accessories that you can purchase. The first is a bag pack and the second is an upgraded longer tether of 100 meters. This is available when you decide to buy the drone and have it with 100 meters of tether instead of the 50 meters.

As for the FIFISH V6, there are 4 available accessories, a VR goggles, a 100 meters’ tether, an HDMI module and spooling reel for the tether.

By the way, as from the 23rd of May till the 7th of June (pre-orders period), the VR is given for free, so it is something worth considering.

There are other accessories for the FIFISH V6 that QYSEA has, like 200 and 300 meters of a tether. However, they will be available later. Having a 200 (or 300) meters of tether allows you to scan wider areas without you moving from the shore or moving the boat.

Gladius Mini LogoFIFISH V6 logo
ProsHaving a dedicated bag packHas VR Goggles
Offering Longer (200 & 300 meters) tethers that most underwater drones have.
Offering a tether reel which can be very helpful when dealing with longer tethers.
ConsDoesn’t have a VR – Can be purchased elsewhere.No dedicated bag pack – However, QYSEA said it will be available soon.
Need to spool the tether manually since there is no spooling reel. It can be an issue with long tethers.

Gladius Mini VS FIFISH V6 – Features

Features are an important issue, and frankly, I don’t think that there is someone better than the other. Both are wonderful underwater drones. And great features like using a VR, Depth lock, social network sharing, and live streaming are few of the features both underwater drones have. And I will continue to our next comparison of the Gladius Mini vs FIFISH V6.

Gladius Mini VS FIFISH V6 – Movement

Gladius Mini vs FIFISH V6 - movement

In this category, the FIFISH V6 gave a knockout – but that is a knockout not only to the Gladius Mini but to all the other underwater drones out there as well.

While the Gladius Mini advertised its capability to tilt by 45 degrees up and down, QYSEA prepared a surprise by allowing the FIFISH V6 to fully tilt by 360 degrees.

But that is not all. As QYSEA called the FIFISH V6 – the only OMNI directional underwater drone.

That’s means, that in addition to 360 degrees of tilting, the FIFISH V6 is even capable of yaw and roll in 360 degrees. Wow!!!

There is no other way to describe these truly amazing movement capabilities, which no other underwater drone can do, including not the new Gladius Mini.

And while Chasing innovation advertises that by being able to tilt the Gladius Mini in 45 degrees is “expanding the scope of photography” – a phrase which I totally agree with. Then, being able to tilt, roll and pitch in 360 degrees basically makes the scope of photography unlimited!

These movement capabilities cannot be ignored – and by far makes the FIFISH V6 one of the best underwater drones today.

Inspections That no-one can Do Except for FIFISH V6

Gladius Mini vs FIFISH V6 - 90 degrees vertically

Well, thanks to the unique movement capabilities of the FIFISH V6, there are some operations that cannot be done by any of the underwater drones today, except for the FIFISH V6.

Imagine you need to find a leakage or a broken piece at the bottom of your structure or maybe even look for something extremely small at the outer bottom side of your yacht. Well, from now on, this is possible and most important, it is very easy. This makes the FIFISH V6 as the most serious inspection equipment.

The possibilities of the FIFISH V6 are truly unlimited, inspecting even big sea creatures from the bottom, or even… well, I think you got the idea. This is trulu AMAZING!!!

But, enough talking, here is a video introducing the movement capabilities of the FIFISH V6

Gladius Mini LogoFIFISH V6 logo
ProsTilt for 45 degrees up and downPitching 360 degrees
Yawing 360 degrees
Rolling 360 degrees
ConsCannot yaw
Cannot roll

Gladius Mini VS FIFISH V6 – Camera Quality

Gladius Mini vs FIFISH V6 - Camera Quality - small

Another super important feature in an underwater drone is the camera quality. No need to explain to you why… right?

As both the Gladius Mini and the FIFISH V6 have a 4K camera, some people think that probably they are having the same quality. However, there is much more than being a 4K camera. So, let’s see what these underwater drones offer us.

One of the most important things about the camera is its CMOS (the camera sensor). Lots of quality depends on it. And for that, the Gladius Mini and the FIFISH V6 are having the same sensor (Both sensors are the 1/2.3-inch size).

But on other parameters which provide a better picture, the FIFISH V6 is better than the Gladius Mini. Let’s take a look.

Aperture and Lighting

Aperture basically means how open the lens of the camera is. A higher aperture (indicated by a small value) means that the picture will have more light in it, and Lower aperture (indicated by a higher value) means the picture will have lower light in it.

Gladius Mini vs FIFISH V6 - aperture reference

The aperture of the FIFISH V6 is 2.5 and for the Gladius Mini is 3.0. They both have a higher aperture which is great, but, the FIFISH V6 has a better one compared to the Gladius Mini. This gap of 0.5 in the aperture will be noticeable, but not as much. And as we look at the lightning specs of the Gladius Mini, since they have a lower aperture of 3.0, I expected them to have stronger led lights, to compensate the lower light. However, their led lights come to a total of 2400 lumens. While, on the other hand, the FIFISH V6, which is having a higher aperture, provides stronger led lights, which comes to a total of 4000 lumens.

Don’t get me wrong, both drones will have good lighting in the picture, but, aperture 2.5 with 4000 lumens will bring a much brighter picture than aperture 3.0 with 2400 lumens. Especially when we take our drones to deep locations, where the lighting conditions are bad. And it will be more effective when inspecting objects deep in the ocean.

Before moving to the next category comparison I think it is very important to see the differences between 2 low light cameras, the PL4 by SwellPro and the GoPro 6. The PL4 has an aperture of 2.o, and the GoPro 6 has an aperture of 2.8.  The FIFISH V6 is somewhere in the middle between these 2. While the Gladius Mini is worse than the GoPro 6 – with an aperture of 3.0.  The differences between these 2 cameras are too noticeable.

Field Of View

Regarding the field of view for each underwater drone, the field of view of the FIFISH V6 is 166 degrees, which is much wider than the Gladius Mini that has a field of view of 95 degrees. A wider field of view is better for video photographing and will provide you more information when doing inspection tasks as well.


Another aspect of the camera is the ISO. In case you are not familiar with it, ISO is a way to compensate the light – in low light scenes. A higher ISO means more light and a brighter image, while lower ISO means less light and darker image.

When I compare the 2 drones, the Gladius Mini has a maximum ISO of 3200, and the FIFISH V6 has a maximum of 6400. Double than the Gladius Mini. Means it can provide brighter images.

Video Resolution

The FIFISH V6 can record in 4K at 25 and 30 frames per second. At 1080p it can shoot in 25, 30, 50, 60, 100 and even 120 frames per second – creating great slow motion videos. And in 720p it can shoot in even slower – 25, 30, 50, 60, 100, 120, 200 and even 240 frames per second.

On the other hand, the Gladius Mini does not support too many frame rates as the FIFISH V6. For 4K is support only 30 frames per second and for 1080p it supports 30, 60 and 120 frames per second. And regarding 720p, well, it does not support that at all.

Gladius Mini vs FIFISH V6 – Other camera features

Before wrapping up about the camera quality, there are several more features that the FIFISH V6 has, like white balancing and EIS (Electronic Image Stabilizer), which the Gladius Mini doesn’t have.

Other than that, both drones use in their app a color correction algorithm in order to correct the colors of the final image. Here is an example of color correction made by the FIFISH V6. On the left is before color correction, and on the right is after the color correction.

FIFISH V6 before and after - small

Gladius Mini LogoFIFISH V6 logo
CMOS1/2.3 Inch1/2.3 Inch
Camera Quality12MP12MP
Light2400 Lumens4000 Lumens
ISOMax ISO of 3200Max ISO of 6400.
Video ResolutionsDoesn’t support 720pSupports 720p up to 240 FPS
Camera Field of View95 degrees166 Degrees
Camera StabilizerNot sure that it hasEIS (Electronic Image Stabilizer)
White BalanceNot sure that it hasSupports white balancing

Gladius Mini VS FIFISH V6 –Other Specs Comparison

Last, in our comparison of the Gladius Mini vs FIFISH V6, I decided to bring some technical specs about both drones. Some of the things are really important. Let’s take a look.

One of the most important aspects is battery life. Well, the battery life of the FIFISH V6 is 4 hours, which is double than the Gladius Mini, that has a battery life of 2 hours.

Also, you can put in the FIFISH V6 a memory card up to 256GB, while in the Gladius MINI you can have it up to 64GB.

Regarding the size and weight, the Gladius Mini is lighter and a bit smaller than the FIFISH V6. Its speed is 2 meters per second, while the speed of the FIFISH V6 is 1.5 meters per second.


Gladius Mini LogoFIFISH V6 logo
Battery Life2 hours4 hours
Speed2 m/s – Can move faster1.5 m/s
SD Card64GBUp to 256GB

Gladius Mini VS FIFISH V6 – It’s all about the money

Or maybe it is now…

To be honest, I was surprised to see the price tag for the Gladius Mini and for the FIFISH V6. I expected them both to be more expensive since they feature great new capabilities (as I mentioned earlier).

The price of the basic package with 50 meters of tether for the Gladius Mini is 1,499$ and for the FIFISH V6 is 1,599$. While as we go further to the 100 meters package the Gladius Mini will cost you a 1,599$ and the FIFISH V6 will cost you 1,799$.

Does it worth you paying an extra 100$ or 200$ (depends on the package), well, that will be up to you to decide. In terms of monetary value, I must say the FIFISH V6 worth every penny.

You won’t go wrong, no matter what you choose.  After all, it depends on what you need it for.

Gladius Mini VS FIFISH V6 – Conclusion

FIFISH V6 winner

I have gone thru many features and specs for both drones, in order to decide which one is better. And even with considering the price tag of both drones, there is truly no place to be wrong here.

First, as I said earlier, both underwater drones are amazing. However, the FIFISH V6 is better than the Gladius Mini in most of the aspects, and in price, they are basically almost the same.

The FIFISH V6 has a better camera quality, has better movement capabilities, has longer battery life and can even go for longer distances (soon, as QYSEA will release their 200 and 300 meters of tethers), and you don’t need to pay much more for it. You can’t ask for a better deal than the FIFISH V6.

You can decide for yourself whether the base station of the Gladius Mini is an advantage for you or not. I considered that as a disadvantage since in my opinion it can seriously risk your drone – But that is up to you to decide.

I hope you enjoyed reading this comparison of the Gladius Mini vs FIFISH V6. Let me know what you think in the comments section below. And till the next time, tight lines.

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6 thoughts on “Underwater Drones: Gladius Mini VS FIFISH V6 – Full Comparison”

  1. Charles W Morton

    Thanks great comparison. I have a Power Ray and it has 2 big drawbacks — It does not hold tilt and it does not have a compass in the unit so it is hard to drive when out of sight. It is “slick” in that other than the tether it does not have protrusions as the FiFish V6 does; that worries me because there is a lot of suspended grass where I use it for reef monitoring. I have had globs of grass tangle on the tether and pull me well off target by the increased drag and ocean currents. The Gladius Mini seems “slicker” and less likely to entangle with suspended grass. I have had grass sucked in by my vertical thruster but Power Vision sent me a screen to for the bottom intake which was unprotected as they appear to be no both the gladium mini and Fifish V6. I am wondering how both of these units perform with suspended grass since most reviews are done in gin clear water.
    That being said I would pass along two hints: (1) Anchor up current from your target and (2) “fly” off the stern of your vessel to minimize the chance of entangling the vessel prop or rudder in you do catch a glob of seagrass on the tether.
    I do like the SD or TF card being either in the controller or base station and not in the drone itself; that way it is not necessary to do a download if moving to a different location — just swap out the cards to keep the data separate (very important for research).
    I did build a tether reel for under $20 that should work for any unit with minor modification, see http://www.flhelp.org/reel. I can wind in my 70 meters of tether in under 2 minutes, but I still like to have someone as a tether monitor.

    1. Thank you very much Charles for your feedback. I think it is very important.
      Regarding the SD card for the Gladius Mini, I think it is also good that it is external. However, having the base station separated can be a problem at some times.
      Thanks for the link of your tether reel DIY. It looks great.

  2. Hello!
    I am thinking of buying either Gladius Mini or the FiFish V6, but I still really can’t decide. I love the freedom of movement with the V6, and it seems better in almost every way. But I have talked to a guy that is very experienced with underwater drones, and he basically said that the Gladius Mini is the best drone in that price range, and that the FiFish V6 is a piece of crap. He said that the V6 doesn’t float (I guess that means that it isn’t neutrally boyant), that there is a jack plug on the remote that easily pulls out and you might loose the drone. And also that the feature showing the position of the drone really doesn’t work very well and that the battery drains very fast. It was basically “Worst rov ever used”.

    So I just want to know if this comparison that you have made is mostly based on theory and specs, or if you have actually tested both drones in “real” conditions, especially in the sea with a bit rougher weather? If so, is your opinion still that the FiFish V6 is better than the Gladius Mini? Thank you very much for your help!


    1. Hi Peter,
      Thank you very much for your comment.
      First, I would say that both the Gladius Mini and the FIFISH V6 are great underwater drones. They both raised the expectations from new ROVs that are about to come.
      Well, regarding what you have been told about the FIFISH V6 is completely untrue.
      For example, it is very easy to see that the FIFISH V6 is naturally floating. You can see at a video review here: https://www.youtube.com/watch?v=jmR1l-5FLAE. Look at a time at 01:33.
      You can also see here https://www.youtube.com/watch?v=wgaSciTnJog on time 02:30 that it is floating (before the ROV was turned on).
      Soon, I hope, we will release our video review for the FIFISH V6 and Gladius Mini.
      Other than that, you can see on YouTube for so many other reviews crowning the V6 as the best underwater drone.

      1. We’ve used both the Gladius mini and the FIFISH V6 and the FIFISH is a clear winner in maneuverability, camera etc. The Fifish is neutrally buoyant but it depends if you are using it in freshwater or seawater as there is an extra weight inserted for seawater use. The first time I used the FIFISH V6 was in a freshwater canal basin, I put it in the water and it promptly sank! I had to use thrust to to maintain neutral buoyancy, the depth lock would not work when using posture lock and moving forward the V6 wanted to climb or submerge. I thought about this and removed the weight for the next trial and it was a different machine, ticked all the boxes and did what it should, a great piece of kit. Battery life has also been good, the FIFISH V6 was a clear winner for us.

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