UV Sterilizer Questions/Myths Answered for Pond & Reef Aquarium

 

Updated 4-6-19

More UV Sterilizer Questions/Myths Answered

In this post I will answer two questions (or possibly “myths”) about the use of UV Sterilizer in Aquariums and Ponds based on email and phone questions I often get.

The questions are:

• Filter placement in relation to UV Sterilizer in ponds.
• Danger of UV Sterilizers to copepods in reef aquariums.

Another article on sterilization in ponds:
Pond Care Information

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(1) Question: Is the UV best placed after or before a filter in a pond?

This question is myth based as there are valid reasons for both applications.
However based on my own use and controlled tests using UV Sterilizers with filters before, after, or not at all, the answer of using the UV Sterilizer after the filter is the better choice.

Let me explain further; when a UV Sterilizer/Clarifier is placed BEFORE a pond filter with no pre-filtration, you do catch “clumped” algae coming from the UV Sterilizer.
This is even more noteworthy when a UV is run a flow rate over 30-35 gph per watt as this higher flow rate will generally not kill algae outright, rather “clump” the algae where it will be expelled from the UV Sterilizer into the pond water column.
Otherwise, this "clumped algae" then it either falls to the bottom of the pond becoming part of the organic mulm/detritus and/or may be picked up by any existing pond pump and filter and removed.

This is the ONLY reason to place a filter after a UV Sterilizer in pond applications.

With previous paragraph in mind, the generally better way to utilize a filter with a UV Sterilizer is to place the filter prior to the UV Sterilizer.
The reason is that turbidity in the water will lower UV Sterilizer effectiveness, and sometimes (based on my tests) to levels that render the UV Sterilizer ineffective.
This often results in the misinformed comment that UV Sterilizers do not work (based on emails and phone calls).

Pre-filtering the water prior to entering the Ultraviolet Sterilizer improves the function of UV Sterilizer by trapping larger particulates, thus allowing more of the UVC irradiation to reach the algae that is causing green water (this also improves destruction of disease pathogens at lower flow rates in both aquariums and ponds).

The other reason for pre-filtration of pond water is I have often have had success in initial clarification of pond water with no pre-filtration, but over time (& sometimes only a few weeks), sludge will build up in the UV Sterilizer.
Often this sludge builds up in recesses around the UV Bulb or quartz sleeve, rendering the UV Sterilizer/Clarifier useless.
This does not mean that pre-filtration does not prevent sludge from building, as it does not, but it most definitely slows down the accumulation of sludge, as well the time it takes to buildup sludge in your pond UV Sterilizer depends on water turbidity, algae, bio load and obviously the quality of your pre-filter.

Where to get:
UV Bulbs; Premium High Efficiency (not the low output UV lamps commonly sold on Amazon or eBay)
Quartz Sleeves
Pond UV Sterilizers

I should note that having both a pre-filter and a post filter (such as a DIY Bio falls or similar filter that fits into the water return prior to re-entering the pond) would be an excellent combination.

(2) Question: Will a UV Sterilizer kill off my beneficial copepod & other crustaceans colonies in my reef tank?

Although not as common a question as the previous question, it still crops up from time to time and I have much harder time understanding why otherwise quite advanced reef keeper fall for what amounts to a UV Sterilizer myth.

As well, my controlled studies admittedly did not include exact counts of copepods with different levels of UV Sterilization, it did show that copepod colonies when properly established never diminished with UV Sterilizer use in reef tanks.
Study Reference:UV Sterilization Studies

There is simple explanation for this result; that is most copepods do not occupy the water column in a healthy colony.

What is a healthy colony?
This is a matter of opinion or experience, but from my perspective a healthy colony is “housed” in large piles of live rock crumbles where many fish such as Mandarin Gobies will seek them out.
As well if you are using a Refugium and want to be certain that all of the copepods/ crustaceans that spill out into the aquarium are not killed, then be sure your UV is on its own filter/pump and not returning water to the aquarium using the same return line as the Refugium.
Finally whenever you dose your aquarium with certain live products such as live planktonic algae or infusoria, you should turn off the UV sterilizer or use a timer that is tied to certain cycles or automatic dosing.

My final comment to this amounts to another aquarium keeping myth.
That is I have had clients/customers that have stood by this myth describe or show me their filter system and I have seen (or had them describe) several of these filter systems that employ micron filters (such as the Ocean Clear) that can easily trap copepods in their micron filters much more effectively than a UV Sterilizer can kill copepods.
In particular adult copepods for which a UV Sterilizer would have to run well under 10 gph per watt to have any chance of destroying any “pods” that get caught in the sterilizer.

As well pre-filtration which should be used in any UV Sterilizer application will trap most adult copepods from entering the Sterilizer.
What makes me laugh here is that these same aquarists often had healthy copepod colonies with the use of these Micron Filters.
I would explain to them that if these filters did not destroy their “pod” colonies, a UV Sterilizer would not either!
I should note that I am not against the use of these micron filters; in fact I think are excellent compliments to other aquarium filters, live rock, and healthy deep sand beds.

Please see this article for more about UV Sterilization and how it works:

UV Sterilization

Recommended Reading:

Common Aquarium Keeping Myths

Aquarium UV Sterilizer Ideas; Filter Combinations, etc.

Unique Aquarium/Pond UV Sterilizer Combinations; Sponge Filter, Power Head, Internal Filter
PART ONE   Updated 9/8/13

This post/article is intended to provide some unique (or "outside the box") combinations of different ways to connect a TRUE UV Sterilizer to an aquarium. Not one of the Internal or Hang On Back UVs flooding the market from China that can at best perform clarification, not true level one sterilization.
Review of: Internal UVs

Most aquarium /pond keepers are aware of the use of canister filters or sump pumps for aquariums or pressurized filter or similar pond filters for ponds. These are the most commonly thought filters for connection of TRUE UV Sterilizers.

Hopefully these ideas I will present will be food for thought for those sitting on the fence as to whether a True UV Sterilizer is feasible for their pond or particularly aquarium. Even small aquarium keepers (such as a 20 gallon) miss the benefits that a UV Sterilizer provides due perceived high costs or filters that cannot accommodate a UV Sterilizer (such as a Power HOB filter like an Aqua Clear).

More information on:
Clear Pond Information
Basic Aquarium Care

Often even a small aquarium keeper can spend more on medications or lost fish than the cost of a UV Sterilizer(& this does not even factor in the heartbreak many feel at the loss of a finned pet). This is not to say that a UV Sterilizer will stop all losses, however I can say emphatically after 30 years of testing and using UV Sterilization in many different aquariums (including controlled tests) that a properly installed and well designed UV Sterilizer will lower the incidence of disease, & increase longevity and over all health by killing many disease pathogens in the water and by improving the Aquarium/pond Redox Balance.
Reference; The importance of Aquarium Redox Balance for Fish Health

An important key is "properly installed and well designed UV Sterilizer" as there are some UV Sterilizers that we have tested that have failed either in effectiveness or in reasonable longevity (such as the popular Submariner/Internal UV Sterilizers that a few stores and web sites are unfortunately promoting). A well made UV Sterilizer will not be effective at flow rates over 25-30 gph per watt for Sterilization (higher for green water control). Some of the more efficient UV Sterilizers such as the TMC Pond Advantage & TMC Vecton have flow patterns that allow the highest possible flow rates while still remaining effective (Bluntly, there is not better line of UVs at any price than the TMC line for Ponds and Aquariums). See the picture to the left which displays what sets a premium high flow design UV Sterilizer apart from the rest (this is a TMC Pond Advantage 25 Watt UV Sterilizer/Clarifier). As well, if the UV Bulbs/Lamps are not changed every six months (the quartz sleeve should also be cleaned at this time). See this website for a cross reference guide if you already have a UV Sterilizer but have failed to change the UVC Bulb in the last six months:
See http://www.uvreplacmentbulbs.com/ for a cross reference directory of premium UV Lamps/Bulbs

Here are a few different ways to connect a UV Sterilizer to your Aquarium or Pond (often quite cheaply too):

Please Click on most pictures to enlarge for a better view

This first combination can be used with many power heads such as the Via Aqua 1300/ SunSun HJ-1542 and Sponge Filter such as the Hydro Sponge #3 pictured here (you can also remove the base for better aesthetics, it was left on in this picture to avoid any confusion). This combination also employs a return and intake adapter.
Product References:
*SunSun HJ-1542 Pump
*Aquarium Sponge Filters
*Plumbing Parts; Return & Intake Adapters


A larger pump such as the Rio 1100 or even the "high end" Rio HF line of Pumps can be substituted for a larger aquarium or pond, as well the Hydro Pond #4 is well design for this application too without need for adaptation for most pumps (see the small inset picture).
Product References:
*Rio/Taam 1100 Pump
*Hydro Pond/Sump Sponge Filters
*Rio HF (High Flow) Pumps

This combination is quite straight forward for use in small aquariums (or even patio ponds that have "walls"). This picture demonstrates a SunSun JP-23 along with a Hydro Sponge #3 Filter and return and intake adapters.
Obviously other power head brands can be adapted as well and although one can purchase the return/intake adapters (see the link in the previous sentence), these can also be a simple DIY project too.
Product References:
*SunSun JP-23 Power Head Pump
*Hydro Sponge #3 Filter


Finally, this combination incorporates the premium, high dwell time Vecton UV for unsurpassed UVC Sterilization up to level 2.
The picture to the left picture demonstrates a Vecton 8 Watt UV, with a Rio 1000, Filter Max #3 Pre-Filter, 5/8" Tubing, and an Intake and Return Adapter.
The small valve included with the Rio 1000 can be used to slow the flow during critical times when a higher level of UV Sterilization is desired (the Rio 100, 1700 also include this valve for larger Vecton installations.
Please click on the picture to enlarge

This last combination is the most effective and yet it is still a very simple application for those not desiring the use of a canister filters or one of the cheap Chinese Internal UV or Hang On UV" imports flooding the market that not only are not all that reliable or durable, but can barely perform UV clarification, yet alone important level one sterilization (or level 2).
Product References:
*TMC High Dwell Time Vecton 8 Watt UV
*Rio/Taam 1000 Pump
*Filter Max #3 Sponge Pre-Filter
*Aquarium Tubing; 5/8" ID

Further Information, References:
*How UVC, Ultraviolet Sterilization Works
*Premium Pond and Aquarium UV Clarifiers, Sterilizers
*Compact Lasting, UV Sterilizers
*UV Replacement Bulbs

Good UV Sterilizer Information

I am writing this post not to brag, but to show the many doubters who continually listen to the anecdotal advice coming from many forums (Yahoo answers in particular) and elsewhere not only about UV Sterilization, but about aquarium keeping and pond keeping in general.
This is an email of a reader who made a long trip down to our warehouse based on reading my aquarium information articles. He had read many of them (the UV Sterilization article in particular).
See: http://www.americanaquariumproducts.com/AquariumUVSterilization.html

He then tried the custom UV Sterilizer and the Wonder Shells (based on information from my article about Aquarium Chemistry KH, Calcium, & Electrolytes), and other methods suggested (not all methods results in the need to buy something either, many are DIY).
See this resource link: "Wonder Shells for Aquarium Minerals"

The email this reader sent me:

"Carl,

I wanted to let you know that your uv sterilizers are great! I have used them over the last week or so and my aquariums have never looked better. Your website speaks the truth. I have spent a lot of money on other filter devices, particularly very expensive protein skimmers, that do not do the same job as a simple uv sterilizer. I like your device more than my Coralife UV as yours has more secure connections and it has a nice flow.
See: http://www.americanaquariumproducts.com/UVSterilizers.html

My reef tank now has pristine, clear water. The inhabitants are doing well.

My discus tank has shown a dramatic improvement. Previously, the water was always slightly cloudy, even with multiple filters and daily water changes. Now, it is much cleaner. My discus are very large and although beautiful, they are sloppy eaters that produce a lot of waste. It makes no sense to keep a bacterial bloom in the water column, as you have pointed out! The color of the discus has improved. Previously, several of them would hang out near the back and they were very shy to eat. Now, with your UV unit, they all come out to the front of the tank and beg me for food. They have never acted that way in the past. They also appeared to have cleared small spots on them that I believe may have been a low grade hexamita infestation.

My planted tank is also improved with high intensity lighting and less algae growth noted. I had occasionally lost fish in this tank when newly added from the store and I believe that the odds of success have been greatly improved.

• http://www.americanaquariumproducts.com/AquariumPlants.html
• http://www.americanaquariumproducts.com/Aquarium_Lighting.html

I wish you well and I hope that others read up on your site. I have been keeping fish for over thirty years and you have taught me a lot. I am reading about tropical fish constantly and it is very seldom that something new comes along. I give you a lot of credit. It is interesting to go back to some of the standard authors and texts in the hobby and compare your notes. I think that you have something to teach them.

I also appreciate your meeting with me to show me your products first hand. Please feel free to stay in touch with me. If you are ever in Roseburg, I would love to show you some very fine aquariums. Keep in the hobby so that you can keep up your skills.

Your friend,
Howard"