UV in a Natural System?

[brettonw]

TL/DR - is UV compatible with a natural approach?

I recently set up a new reef. It's not my first rodeo despite a 10+ year hiatus. I'm a big fan of natural systems for managing nutrients and whatnot (aka what actually happens in the reef), and this mostly means an effort to include diverse organisms at all levels of the food processing stage, and nutrient export via macro-algae in the sump. I run a skimmer because I feed my tank robustly. At each phase of the tank, we encounter a problem and then say, "ok, what eats that?'

I contrast this with intervention and engineering - changing water or adding chemistry supplements are interventions, and fancy systems like skimmers, reactors, and the Apex controller are engineering. I use an Apex Neptune with a hack to use Home Assistant to monitor and control my system's temperature, pH, and salinity. My goal is low intervention, but I'm not religious about it to the point of not doing water changes, etc.

So with all of this, I bought a pretty blue tang. Everybody knows where this is headed. I was stupid and didn't keep it quarantined long enough. It looked healthy after a few days and was eating, so... Within a few days of adding it to the Display Tank (DT) it showed white spots, and over the course of the next week got better, then worse, then better, then died. I have no idea whether the parasite was already in the tank, came from this fish, or what. The idea of "managing" marine parasite infections with "good husbandry" went out the window, cause it's in my DT now.

My other fish are showing signs of distress, so I'm planning to try to catch them tonight and move them to quarantine with copper, leaving the DT fallow for the recommended period. This doesn't seem like a manageable long-term alternative if I want to add anything to the tank, though. I'll need separate quarantine tanks for inverts and fish, and this ultimately feels like a lot of intervention with little guarantee of success. One mistake and everything is in peril again.

Is there a test kit for ich or marine velvet (LOL)? Does anything "eat" them?

Wifey suggested we look at UV systems to help manage parasites in the future, as we certainly intend to add more life over time. I haven't used one before, but the level of UV needed to manage marine parasites is more than sufficient to kill all other life in the water column. This means no more diatoms and planktonic stuff that are one of the primary sources of food for the army of snails, hermits, 'pods, and filter feeders that currently occupy the surfaces of my tank. Also, since the UV doesn't address the source of the parasite (the sandbed), it's just a mitigation strategy to reduce the prevalence of the parasite, i.e. if I turn it off the parasite can return in full force.

So I'm alarmed by this possibility. If I remove the natural source of food, is it even possible to replace it with something to keep all these critters that are part of the natural system from dying or disappearing? Is it actually that dire, am I overreacting?

 

[MnFish1]

TL/DR - is UV compatible with a natural approach?

I recently set up a new reef. It's not my first rodeo despite a 10+ year hiatus. I'm a big fan of natural systems for managing nutrients and whatnot (aka what actually happens in the reef), and this mostly means an effort to include diverse organisms at all levels of the food processing stage, and nutrient export via macro-algae in the sump. I run a skimmer because I feed my tank robustly. At each phase of the tank, we encounter a problem and then say, "ok, what eats that?'

I contrast this with intervention and engineering - changing water or adding chemistry supplements are interventions, and fancy systems like skimmers, reactors, and the Apex controller are engineering. I use an Apex Neptune with a hack to use Home Assistant to monitor and control my system's temperature, pH, and salinity. My goal is low intervention, but I'm not religious about it to the point of not doing water changes, etc.

So with all of this, I bought a pretty blue tang. Everybody knows where this is headed. I was stupid and didn't keep it quarantined long enough. It looked healthy after a few days and was eating, so... Within a few days of adding it to the Display Tank (DT) it showed white spots, and over the course of the next week got better, then worse, then better, then died. I have no idea whether the parasite was already in the tank, came from this fish, or what. The idea of "managing" marine parasite infections with "good husbandry" went out the window, cause it's in my DT now.

My other fish are showing signs of distress, so I'm planning to try to catch them tonight and move them to quarantine with copper, leaving the DT fallow for the recommended period. This doesn't seem like a manageable long-term alternative if I want to add anything to the tank, though. I'll need separate quarantine tanks for inverts and fish, and this ultimately feels like a lot of intervention with little guarantee of success. One mistake and everything is in peril again.

Is there a test kit for ich or marine velvet (LOL)? Does anything "eat" them?

Wifey suggested we look at UV systems to help manage parasites in the future, as we certainly intend to add more life over time. I haven't used one before, but the level of UV needed to manage marine parasites is more than sufficient to kill all other life in the water column. This means no more diatoms and planktonic stuff that are one of the primary sources of food for the army of snails, hermits, 'pods, and filter feeders that currently occupy the surfaces of my tank. Also, since the UV doesn't address the source of the parasite (the sandbed), it's just a mitigation strategy to reduce the prevalence of the parasite, i.e. if I turn it off the parasite can return in full force.

So I'm alarmed by this possibility. If I remove the natural source of food, is it even possible to replace it with something to keep all these critters that are part of the natural system from dying or disappearing? Is it actually that dire, am I overreacting?

While I laud your desire to have a 'natural' tank - as you're seeing - it's quite difficult - especially with higher stocking density/large fish. A 'natural tank' also has multiple definitions. IMHO - to specifically answer your question - a UV will first kill bacteria, in the tank - with larger units - it can help keep down the number of parasites - though there is a little debate as to how effective this actually is. So if your idea is to have many/all of the bacteria 'in the ocean' in your tank - a UV will dramatically change this. That said - I'm not sure there is a lot of good data out there suggesting that it's possible to have anything close to those levels in ANY reef tank.

If you are going to treat all of your fish (with copper in a hospital tank) - for 30 days, you may want to add 2 prazipro treatments 8 days apart - per the protocol at the top of the forum. This alone should remove all of the parasites from the fish - and the fallow period will remove them from the tank. You would then need to treat any new fish in the same manner - before adding to your tank.

There is nothing 'un-natural' about a protein skimmer IMHO. The balancing act with the type of tank you're attempting, is that most fish do best (with illness, etc) - with pristine water conditions - and not using some of the equipment makes that more difficult.

Best of luck - and sorry about your fish!! @atoll may have some words of wisdom

 

[brettonw]

While I laud your desire to have a 'natural' tank - as you're seeing - it's quite difficult - especially with higher stocking density/large fish. A 'natural tank' also has multiple definitions. IMHO - to specifically answer your question - a UV will first kill bacteria, in the tank - with larger units - it can help keep down the number of parasites - though there is a little debate as to how effective this actually is. So if your idea is to have many/all of the bacteria 'in the ocean' in your tank - a UV will dramatically change this. That said - I'm not sure there is a lot of good data out there suggesting that it's possible to have anything close to those levels in ANY reef tank.

I'm not trying to be pedantic here, but my main assertion is that it's easiest to keep animals alive in environments that closely match their natural habitat. Imagine an alien race trying to keep humans alive in an all-oxygen atosphere, or one in which all bacteria are eliminated through sterlization procedures (we need some of them).

When I first started in this hobby, Ron Shimek was advocating lights and feeding regimens that mimicked the natural reef but had never been tried before, and hobbyists started enjoying unprecedented success. So I see that as good data. John Tullock's book covered it pretty well.

The tank environment gives parasites an unnatural edge in their fight for survival, so I see UV as a potential way to mitigate that, but at the cost of the rest of the habitat?

If you are going to treat all of your fish (with copper in a hospital tank) - for 30 days, you may want to add 2 prazipro treatments 8 days apart - per the protocol at the top of the forum. This alone should remove all of the parasites from the fish - and the fallow period will remove them from the tank. You would then need to treat any new fish in the same manner - before adding to your tank.

Affirmative.

There is nothing 'un-natural' about a protein skimmer IMHO. The balancing act with the type of tank you're attempting, is that most fish do best (with illness, etc) - with pristine water conditions - and not using some of the equipment makes that more difficult.

I agree in general, I don't mean to imply skimmers are "unnatural". It's just that lots of filtration equipment designed by engineers solves one problem in a vertical way, without considering the balance of everything else that system affects. You end up having to add more and more equipment to solve the next problem in the chain, when starting out with a natural habitat would work. Some machines are happy accidents that do a good job of balancing out (like calcium reactors). Skimmers are a natural process that is just accelerated for purpose of removing extra compounds that would eventually just break down in the water.

UV isn't like this, it seems. It's a kill-all so I can keep fish, which sounds kind of boring to me (looking at the tank at night with a flashlight is a delight).

 

[zdrc]

I would like to point out that attaining "naturalness" in a home aquarium is fundamentally impossible just due to the size of aquariums when compared to a real ocean reef. The depth and width of diversity naturally present within the ocean simply cannot be replicated in the aquarium because there's just not enough space. Some large public aquariums might get close, but not that close.

I do agree that maintaining an overly sterile environment can cause real problems in the long run, and I have a low opinion of unnecessary water additives.

I find it funny that water changes would be considered unnatural. Does a 4 ft section of a real reef have the same few hundred gallons of water recirculated over and over across it? No, it gets fresh saltwater every few seconds. IMO continuous water changes would make for a more natural aquarium than no water changes.

 

[MnFish1]

I'm not trying to be pedantic here, but my main assertion is that it's easiest to keep animals alive in environments that closely match their natural habitat. Imagine an alien race trying to keep humans alive in an all-oxygen atosphere, or one in which all bacteria are eliminated through sterlization procedures (we need some of them).

When I first started in this hobby, Ron Shimek was advocating lights and feeding regimens that mimicked the natural reef but had never been tried before, and hobbyists started enjoying unprecedented success. So I see that as good data. John Tullock's book covered it pretty well.

The tank environment gives parasites an unnatural edge in their fight for survival, so I see UV as a potential way to mitigate that, but at the cost of the rest of the habitat?



Affirmative.



I agree in general, I don't mean to imply skimmers are "unnatural". It's just that lots of filtration equipment designed by engineers solves one problem in a vertical way, without considering the balance of everything else that system affects. You end up having to add more and more equipment to solve the next problem in the chain, when starting out with a natural habitat would work. Some machines are happy accidents that do a good job of balancing out (like calcium reactors). Skimmers are a natural process that is just accelerated for purpose of removing extra compounds that would eventually just break down in the water.

UV isn't like this, it seems. It's a kill-all so I can keep fish, which sounds kind of boring to me (looking at the tank at night with a flashlight is a delight).

I will make a couple quick points:

1. The most natural way to keep a tank would be large daily water changes - which is what happens in the ocean every instant.
2. Many natural aquarium keepers MAY completely disagree with any type of medicated quarantine - as it affects both the fish's immune system - as well as to a degree their microbiome.
3. Like I said in my original post - its a laudable goal - BUT - the reason for all of the equipment, etc etc - is because in nearly every instance, it helps keep the tank inhabtants more healthy and disease resistant in the first place.

The ocean has its own 'natural' filtering mechanisms, namely - corals, etc etc. Parasites have parasites that keep them in check, and, as you said, they are diluted out. Back to your original question - if you want to keep a 'natural' aquarium, a UV would not be a positive choice for me. I would focus on well fed, healthy fish - and assuming you are going to have corals, etc - sourcing them from a known supplier, etc.

 

[MnFish1]

UV isn't like this, it seems. It's a kill-all so I can keep fish, which sounds kind of boring to me (looking at the tank at night with a flashlight is a delight).

PS - sorry - I don't understand this. I thought you were asking about whether (paraphrased) UV would be a reasonable addition to a 'natural aquarium'. If you believe that UV is a 'Kill All' - doesn't that (kind-of) answer your question? I.e. you will decrease the amount of life-forms in your tank?

 

[Piscans]

sure, when waves wash water on land, the sand probably picks up some of the dinos and stuff, that is killed by the uv by the sun. i run uv

 

[flashsmith]

I've been running uv in 2 systems for the last year. About a month ago I decided to try to go "natural" to save some money on my electric bill for one and to eliminate some equipment maintenance. I haven't added livestock other than an occasional clean up crew restock in quite a while so I thought I would give it a go without uv. Within a week I had a pretty bad bacteria outbreak in both tanks. I tried a couple different things with no results. I dose but don't use any miracle cures or snake oils in my tanks. I turned the UV back on and within a day both tanks were crystal clear. Lesson learned I won't run a tank without one. I think UV is better than adding this and that and trying to see what sticks. Yes it probably kills some good things but to me that's worth the trade off of having a crystal clear tank all the time without chasing gremlins with additives.

 

[Tamberav]

My bet is @Paul B would say no as killing the parasites with UV goes against trying to make the fish immune. I suppose parasites are natural as well.

I don’t mind UVs but do be mindful it may not solve your issues with parasites at all.

 

[ReefGeezer]

Many of the beneficial bacteria that are present are on the substrate and will never be impacted by the UV. Some beneficial bacteria are free floating/swimming, and could be killed by the UV. However, they return the nutrients that were bound before the UV killed them to the water, and more bacteria will grow using them. On the other hand, using a UV for parasite control is usually not very effective.

There is nothing natural about a reef tank. Using biology and technology to make the environment's parameters as close to natural as possible and to maintain stability is about as close as we can get. This extends to everything in the system, measurable or not. At the risk of offending the reefing gods, I'll say that I've also noticed that parasites are not much of a problem when I am successful at keeping the environment stable and in good shape.

Here's some examples...
Biology: Live Rock & Sand; Lots of Corals; Carbon Dosing; Phytoplankton; Fresh foods
Technology: Protein skimmer; Dosing to provide needed water chemistry control; Water changes; Dosing to maintain nutrient levels

 

[brettonw]

PS - sorry - I don't understand this. I thought you were asking about whether (paraphrased) UV would be a reasonable addition to a 'natural aquarium'. If you believe that UV is a 'Kill All' - doesn't that (kind-of) answer your question? I.e. you will decrease the amount of life-forms in your tank?

This is my question. This is what it sounds like to me. Am I wrong?

 

[brettonw]

I would like to point out that attaining "naturalness" in a home aquarium is fundamentally impossible just due to the size of aquariums when compared to a real ocean reef. The depth and width of diversity naturally present within the ocean simply cannot be replicated in the aquarium because there's just not enough space. Some large public aquariums might get close, but not that close.

Aknowledged. I didn't mean this to be a debate over whether a "natural" system was the right way to go. Just a question if using UV would be so effective that the critters relying on stuff in the water would be able to survive.

I find it funny that water changes would be considered unnatural. Does a 4 ft section of a real reef have the same few hundred gallons of water recirculated over and over across it? No, it gets fresh saltwater every few seconds. IMO continuous water changes would make for a more natural aquarium than no water changes.

I mean, yes, but... Water changes are intervention, not unnatural. I might debate that replacing water with sterile water isn't what happens in the reef either. The water over one section of the reef doesn't magically transport to the middle of the Atlantic ocean every 10 seconds, it moves to the next 4ft section of the reef. There are multiple reasons the ocean has a continuous supply of "clean" water, one of them is that the life in the reef consumes the stuff in the water.

 

[killer2001]

The definition of a "natural" system to me would be, constant large water changes (preferably with NSW), no UV, proper diet/nutrition for each individual fish and no quarantine / medications. Live Rock + Sand is a must.

 

[brettonw]

Many of the beneficial bacteria that are present are on the substrate and will never be impacted by the UV. Some beneficial bacteria are free floating/swimming, and could be killed by the UV. However, they return the nutrients that were bound before the UV killed them to the water, and more bacteria will grow using them. On the other hand, using a UV for parasite control is usually not very effective.

I'm not really talking about bacteria here. Mostly I'm concerned about micro-flora and fauna that function as a food chain, dinos, pods, etc. Conceptually anything that has a pelagic component of its lifecycle would be killed by a high intensity UV system, and so any role that critter plays either as a consumer or as food is eradicated.

There is nothing natural about a reef tank. Using biology and technology to make the environment's parameters as close to natural as possible and to maintain stability is about as close as we can get. This extends to everything in the system, measurable or not. At the risk of offending the reefing gods, I'll say that I've also noticed that parasites are not much of a problem when I am successful at keeping the environment stable and in good shape.

I'm good with "as close as we can get". I'm just taking the approach that many thousands of years of nature are probably better at solving this than mere human engineers - I don't have any hubris that I know exactly what is right. I have perfectly stable water to the best of my ability to tell, test kits, controllers, etc. all exactly where the recommendations say they should be; but I've got a dead fish and I don't want that to happen again. So... I'm entertaining the notion of using UV, possibly at the expense of many other aspects of my system.

If you use UV, do you have a thriving copepod/amphipod/filter-feeder/snail/crab/shrimp population in your tank?

 

[ReefGeezer]

I'm not really talking about bacteria here. Mostly I'm concerned about micro-flora and fauna that function as a food chain, dinos, pods, etc. Conceptually anything that has a pelagic component of its lifecycle would be killed by a high intensity UV system, and so any role that critter plays either as a consumer or as food is eradicated.



I'm good with "as close as we can get". I'm just taking the approach that many thousands of years of nature are probably better at solving this than mere human engineers - I don't have any hubris that I know exactly what is right. I have perfectly stable water to the best of my ability to tell, test kits, controllers, etc. all exactly where the recommendations say they should be; but I've got a dead fish and I don't want that to happen again. So... I'm entertaining the notion of using UV, possibly at the expense of many other aspects of my system.

If you use UV, do you have a thriving copepod/amphipod/filter-feeder/snail/crab/shrimp population in your tank?

It is very difficult for a hobby grade UV to create the exposure required to kill complex organisms. Bacteria, you bet. Viruses, yep. Free swimming single cell parasites and plankton, maybe. Anything more complex, probably not. At best it might limit the population slightly.

To answer one of your original questions... Some corals and filter feeders eat the parasites in one of their stages of life.

 

[Spare time]

I'm not trying to be pedantic here, but my main assertion is that it's easiest to keep animals alive in environments that closely match their natural habitat. Imagine an alien race trying to keep humans alive in an all-oxygen atosphere, or one in which all bacteria are eliminated through sterlization procedures (we need some of them).

When I first started in this hobby, Ron Shimek was advocating lights and feeding regimens that mimicked the natural reef but had never been tried before, and hobbyists started enjoying unprecedented success. So I see that as good data. John Tullock's book covered it pretty well.

The tank environment gives parasites an unnatural edge in their fight for survival, so I see UV as a potential way to mitigate that, but at the cost of the rest of the habitat?



Affirmative.



I agree in general, I don't mean to imply skimmers are "unnatural". It's just that lots of filtration equipment designed by engineers solves one problem in a vertical way, without considering the balance of everything else that system affects. You end up having to add more and more equipment to solve the next problem in the chain, when starting out with a natural habitat would work. Some machines are happy accidents that do a good job of balancing out (like calcium reactors). Skimmers are a natural process that is just accelerated for purpose of removing extra compounds that would eventually just break down in the water.

UV isn't like this, it seems. It's a kill-all so I can keep fish, which sounds kind of boring to me (looking at the tank at night with a flashlight is a delight).

We don't keep these animals in an environment even remotely similar to their natural habitat. It's simply not possible. Skimmers are not natural and are act like a sterilizer, removing large swaths of bacteria and what not from the water column. Do not try for an all natural approach. Try for what keeps the organisms healthiest (which often is not the most natural environment)

 

[MnFish1]

Aknowledged. I didn't mean this to be a debate over whether a "natural" system was the right way to go. Just a question if using UV would be so effective that the critters relying on stuff in the water would be able to survive.



I mean, yes, but... Water changes are intervention, not unnatural. I might debate that replacing water with sterile water isn't what happens in the reef either. The water over one section of the reef doesn't magically transport to the middle of the Atlantic ocean every 10 seconds, it moves to the next 4ft section of the reef. There are multiple reasons the ocean has a continuous supply of "clean" water, one of them is that the life in the reef consumes the stuff in the water.

This is a good point - many of the 'water changes' occurring on the reef result in upwelling of plankton, etc. However - It also suggests your goal (which is poorly defined - not by you - but in general) - a 'natural aquarium'. IMHO - as others have said - there is no such thing

 

[MnFish1]

We don't keep these animals in an environment even remotely similar to their natural habitat. It's simply not possible. Skimmers are not natural and are act like a sterilizer, removing large swaths of bacteria and what not from the water column. Do not try for an all natural approach. Try for what keeps the organisms healthiest (which often is not the most natural environment)

Actually - it would be interesting - much like the people that keep their 'aquarium' @brandon429 - in a jar - but merely use 100% water changes. This is perhaps the closest one could get to a 'natural aquarium'. To get back to the OP - A UV is not the way

 

[ReefGeezer]

To answer one of your original questions... Some corals and filter feeders eat the parasites in one of their stages of life.

Yea, replying to myself, but I had a thought. Imagine that! The Op might think about adding soft corals, clams, and other filter feeders while the tank is fallow. I think these organisms might help keep the population of free swimming parasites low naturally via predation.

 

[MnFish1]

I'm not really talking about bacteria here. Mostly I'm concerned about micro-flora and fauna that function as a food chain, dinos, pods, etc. Conceptually anything that has a pelagic component of its lifecycle would be killed by a high intensity UV system, and so any role that critter plays either as a consumer or as food is eradicated.



I'm good with "as close as we can get". I'm just taking the approach that many thousands of years of nature are probably better at solving this than mere human engineers - I don't have any hubris that I know exactly what is right. I have perfectly stable water to the best of my ability to tell, test kits, controllers, etc. all exactly where the recommendations say they should be; but I've got a dead fish and I don't want that to happen again. So... I'm entertaining the notion of using UV, possibly at the expense of many other aspects of my system.

If you use UV, do you have a thriving copepod/amphipod/filter-feeder/snail/crab/shrimp population in your tank?

Microfloura are 'bacteria'. UV will also (depending on the size - you said you wanted to look into your tank with a flashlight at night - UV IMHO - will SOMEWHAT - diminish those organisms. Im going to just say - you seem to be wanting to straddle the issue. I want my fish disease free - but I want a 'natural tank'. Bluntly - and some will disagree - you are not going to get a duplicate of nature in a reef tank. It's an impossible goal. Your water will have dissolved organics, etc - and other unmeasurable things. Again Just My opinion. Given your plan for treating your existing fish - the way you described - there is no reason for a UV. Thats the original question. Thats the answer IMHO