Pentair or Aqua UV

[ReeferTCG]

Hello reefers,

Trying to get real user feedback. Pentair or aqua UV. Im designing my new tank and trying to decide which brand to go with.

Second question, 50 W or 80 W for a 243 display 300g total? 50 is rated for that size but I've heard to go oversize with UV. Looking to keep parasite for fish at bay.

 

[mmorrison55]

How many returns are you running? I ask because you may want more than 1 uv if you run dual return pumps.

I don’t have any experience with Pentair, but I hear they are good. they seem to be more oversized than Aquauv. I assume that is why they have a recommended lower flow rate requirement vs the same size Aquauv, but i don’t really know if this is the reason, just my guess.

 

[UncommonSense]

Pentair or aqua UV

Pentaire rates their units to 2x the UV dosage of Aqua UV, which subsequently means their recommended flow rates are lower for an equivalent wattage sterilizer… this may benefit you in a dual return pump (two return plumbing runs with half of typical flow through each) scenario when targeting a higher UV dose!

 

[Beauty of the Reef]

In my opinion. Pentair is the winner when it comes to down to protozan kill.

AquaUV published data in the 90mJ/cm3 for disease, whereas Pentair published for 180mJ/cm3 being more suited for parasite control.

Some studies have found that 90mJ/cm3 is not sufficient. Do some research if you so may.

At the end of the day, we need to know the use case. Water Clarity VS disease management.

Water Clarity, AquaUV

Disease Managment = Pentair

Both will need yearly bulb changes, and be sure to inspect/replace the quartz tube in the Pentair. They have had a history of failure.

 

[ReeferTCG]

Thanks for the great feedback!

 

[AviR]

My pentair after a while broke down/melted (maybe could call it deteriorated) through the outside wall and water started flowing out of it . And I did replace the and quartz I believe

 

[ReeferTCG]

My pentair after a while broke down/melted (maybe could call it deteriorated) through the outside wall and water started flowing out of it . And I did replace the and quartz I believe

That is my only worry! Many great things then stories of just disaster with pentair

 

[Beauty of the Reef]

That is my only worry! Many great things then stories of just disaster with pentair

One Thing to consider is the environment. UVC photons love to attack chemical bonds.

Pentair offers a 3 year housing warranty, while AquaUV offers a lifetime warranty.

It seems that AquaUV found the better material, but I’m sure there’s some science or reason behind it, otherwise the Pentair being as established of a company wouldn’t still be using what they are.

 

[A_Blind_Reefer]

Have you looked a lifeguard? They have a replaceable (sacrificial) liner to keep the housing in decent shape. You basically replace the liner when you replace the lamp.

I have mixed feelings about melting housings and sacrificial liners. I only hear people talking about the melted housings leaking or being translucent (light shining through). I’ve never heard anyone talk about what the melted housing (or sacrificial liner for that matter) leeches into the tank. My decrepit brain says neither is good for the tank inhabitants. Maybe @Randy Holmes-Farley can guess what could possibly enter the water column from melting or disintegrating black or white abs/pvc?

 

[ReeferTCG]

Have you looked a lifeguard? They have a replaceable (sacrificial) liner to keep the housing in decent shape. You basically replace the liner when you replace the lamp.

I have mixed feelings about melting housings and sacrificial liners. I only hear people talking about the melted housings leaking or being translucent (light shining through). I’ve never heard anyone talk about what the melted housing (or sacrificial liner for that matter) leeches into the tank. My decrepit brain says neither is good for the tank inhabitants. Maybe @Randy Holmes-Farley can guess what could possibly enter the water column from melting or disintegrating black or white abs/pvc?

I have not look at that one let me check it out

 

[ReeferTCG]

One Thing to consider is the environment. UVC photons love to attack chemical bonds.

Pentair offers a 3 year housing warranty, while AquaUV offers a lifetime warranty.

It seems that AquaUV found the better material, but I’m sure there’s some science or reason behind it, otherwise the Pentair being as established of a company wouldn’t still be using what they are.

Warranty would be a good one to check thanks did not think of that!

 

[Royce024]

I would recommend lifegard too. I replace the inner sleeve yearly. Been using the sterilizer for 6-7 years now without issues.

 

[Ryan - Serious Reefs]

I think it comes down to a few things:

• Does it accomplish the intended goal? Double the UV dose is a material difference. I won’t claim to know exactly what the effective dose really needs to be, but going too low can turn an expensive tool into an expensive toy. Going higher is obviously the lower risk direction, but this is a tough one because you’re ultimately relying on brand claims and other users’ experience. The available science is pretty murky.
• Does it fit? AquaUV is substantially smaller, so it will work in more installations.
• Flow rate? AquaUV requires higher flow rates and likely needs to be monitored more closely. Since the dose is already 50% lower, getting the flow rate right probably matters even more.
• Cost? AquaUV is considerably cheaper. Ultimately, the best parasite-control solution that fits the budget is probably the right answer.
• Longevity? This is the first time I’ve heard of Pentair units degrading over time. I’ve used many of them for 4–6 years on various tanks and never experienced a structural or ballast issue. Most of those were 50-watt HO units. I know Than uses a HO units as well, and I don’t recall him ever mentioning this type of problem.

If the strength of the UV were degrading the plastic, I’d expect it to happen at a relatively similar rate across a meaningful percentage of users, with some kind of predictable failure range. At least from what I’ve seen, that doesn’t appear to be the case.

 

[ReeferTCG]

I think it comes down to a few things:

• Does it accomplish the intended goal? Double the UV dose is a material difference. I won’t claim to know exactly what the effective dose really needs to be, but going too low can turn an expensive tool into an expensive toy. Going higher is obviously the lower risk direction, but this is a tough one because you’re ultimately relying on brand claims and other users’ experience. The available science is pretty murky.
• Does it fit? AquaUV is substantially smaller, so it will work in more installations.
• Flow rate? AquaUV requires higher flow rates and likely needs to be monitored more closely. Since the dose is already 50% lower, getting the flow rate right probably matters even more.
• Cost? AquaUV is considerably cheaper. Ultimately, the best parasite-control solution that fits the budget is probably the right answer.
• Longevity? This is the first time I’ve heard of Pentair units degrading over time. I’ve used many of them for 4–6 years on various tanks and never experienced a structural or ballast issue. Most of those were 50-watt HO units. I know Than uses a HO units as well, and I don’t recall him ever mentioning this type of problem.

If the strength of the UV were degrading the plastic, I’d expect it to happen at a relatively similar rate across a meaningful percentage of users, with some kind of predictable failure range. At least from what I’ve seen, that doesn’t appear to be the case.

Ryan thanks for the response! It does help a lot in the decision making.
My goal is parasite control for sure. Maybe fitting a smaller pentair might be a good play for the purpose could work.
Great point of degrading material for every UV filter at the same rate. Quality control sure.. but its the same material for everyone so same material should degrade at similar rate!

 

[W31Olds]

Some of the housing problems may be related to improper use. UV's generate heat so I always turn mine off if my pump is off. Mounting units vertically can also allow the water in the unit to drain which may cause problems if the UV is on. I just changed the Bulb in my 80 watt Pentair and inspected the housing and did not see any evidence of housing erosion or thin spots,

 

[Ryan - Serious Reefs]

As for the Lifegard units, they could be great units but I’ve never put a lot of thought into them. Most of their product line seems focused on freshwater and ponds, while the reef crossover products tend to look like aging, entry-level gear. Generally speaking, I’ve also found that companies with very broad product offerings sometimes treat UV as more of a “me too” category and may not have deep expertise in the application.

That said, upon reflection, Pentair and AquaUV are also heavily focused on freshwater and ponds, so that criticism probably isn’t entirely fair.

At first glance, the Pro Max series looks a lot like a Pentair HO unit. The challenge is figuring out which one is right for the tank because their website provides sizing and flow recommendations for ponds and “aquariums,” but nothing specifically for saltwater. The recommendations also focus on bacteria and algae, with no mention of parasites or protozoa. This is where the lack of specialized focus and applicational expertise comes in for me.

That said, they could be great units and simply suffer from a poor website and inadequate product descriptions. It’s likely that, with some research, you could estimate the appropriate dose and flow rates by comparing them with similarly sized units from other manufacturers.

If those numbers line up, the Lifegard units could be a less expensive alternative and may even offer some functional advantages.

 

[Ryan - Serious Reefs]

Some of the housing problems may be related to improper use. UV's generate heat so I always turn mine off if my pump is off. Mounting units vertically can also allow the water in the unit to drain which may cause problems if the UV is on. I just changed the Bulb in my 80 watt Pentair and inspected the housing and did not see any evidence of housing erosion or thin spots,

Sounds plausible.

I’ve taken thousands of support calls or escalations where the problem wasn’t obvious. When an issue only affects a small subset of users, we naturally assume it’s a quality control problem or that something is wrong with the product or method.

But more often than not the issue ends up being something specific to the application of the product or method.

In this case, I believe the UV is either going to materially damage the plastic or it isn’t. There may be some variation in how long that takes based on turbidity and potentially a few other factors, but ultimately they should all end up in the same place. That doesn't seem to be the case.

 

[A_Blind_Reefer]

In this case, I believe the UV is either going to materially damage the plastic or it isn’t. There may be some variation in how long that takes based on turbidity and potentially a few other factors, but ultimately they should all end up in the same place. That doesn't seem to be the case.

This is logical….until someone gets bought out, decides to cut corners along the line, or there’s material changes due to supply chain/cost issue, etc.

Also, the whole internet lore thing…there are threads and videos floating around of different uv systems with these issues. As with anything on the internet who knows the background. Was the uv dry run for days on end? Was the flow so abysmal that it did not provide adequate cooling? Were there air pockets within the fluid chamber? Was some medication/chemical dosed that may react with uv and certain plastics? Whatever the case is there are a few out there (some brands more than others).

For me, when I rebuilt a Lifegard the first time and saw how much of the sacrificial white pvc liner was eroded and missing I thought to myself…..this can’t be great. Even portions of the black housing (where the liner didn’t fully cover) had changed from the smooth glossy black finish, to a dull sandblasted like texture.Yet I continued using it until the second rebuild. That time it hit me. All this eroded pvc has to be circulating through the system, and it can’t be a good thing. So it’s completely rebuilt and sitting in the garage.

Personally, I think (just my opinion) that it might not be a great idea for me to run certain uv systems 24/7 just because it feels good. Maybe there’s a difference in material between “hobby grade” and “industrial grade” units in this regard……maybe not.

That said, there are certainly a ton of units out there (some decades old Emperer/Pentair) with no issues at all. Kinda like those Blue Sky Aquariums…..some sprung a leak, some have yet to spring a leak, and some will never leak.

 

[UncommonSense]

This is logical….until someone gets bought out, decides to cut corners along the line, or there’s material changes due to supply chain/cost issue, etc.

Also, the whole internet lore thing…there are threads and videos floating around of different uv systems with these issues. As with anything on the internet who knows the background. Was the uv dry run for days on end? Was the flow so abysmal that it did not provide adequate cooling? Were there air pockets within the fluid chamber? Was some medication/chemical dosed that may react with uv and certain plastics? Whatever the case is there are a few out there (some brands more than others).

For me, when I rebuilt a Lifegard the first time and saw how much of the sacrificial white pvc liner was eroded and missing I thought to myself…..this can’t be great. Even portions of the black housing (where the liner didn’t fully cover) had changed from the smooth glossy black finish, to a dull sandblasted like texture.Yet I continued using it until the second rebuild. That time it hit me. All this eroded pvc has to be circulating through the system, and it can’t be a good thing. So it’s completely rebuilt and sitting in the garage.

Personally, I think (just my opinion) that it might not be a great idea for me to run certain uv systems 24/7 just because it feels good. Maybe there’s a difference in material between “hobby grade” and “industrial grade” units in this regard……maybe not.

That said, there are certainly a ton of units out there (some decades old Emperer/Pentair) with no issues at all. Kinda like those Blue Sky Aquariums…..some sprung a leak, some have yet to spring a leak, and some will never leak.

This inspired me to do another round of research to see if anyone’s making a UV sterilizer with all wetted parts (less seals and quartz sleeve) being titanium… (not prone to UV degradation)

As it turns out, Deltec & Abyzz are collaborating, and have 48W and 80W titanium bodied UV sterilizers which were “2 to 3 months out from release” in March 2026, now 2-3 months behind schedule… so hopefully they will announce something soon?