UV Sterilizer......pros and cons ?

[liveforphysics]

"Marine food chains


The oceanic food chain begins with microscopic drifting plants called phytoplankton. Phytoplankton are found close to the surface of the water where there is adequate sunlight for photosynthesis.

Phytoplankton are eaten by tiny floating animals known as zooplankton. Zooplankton include the larvae of crabs, jellyfish, corals and worms, as well as adult animals like tiny shrimps, copepods and euphausiids. They keep buoyant with the help of gas-filled chambers and oil droplets which reduce their density.

Zooplankton in turn are food for fish. Big fish eat smaller fish. At the top of the food chain are large predatory fish like sharks, mammals like seals, and seabirds. A very large fish, the whale shark, and some very large mammals, the baleen whales, feed directly on zooplankton."



This is a real basic snippet about the roll of phytoplankton from this fairly weak site http://www.panda.org/news_facts/education/middle_school/habitats/oceans/index.cfm (again, I was just looking for something as basic as posible).


Now, useing electricty to generate light, or generate water movement seems to be working towards makeing a more natural/realistic enviroment. Its kinda a weak substution, but its in the right direction working towards nature.

Useing UV to kill everything in the water, perticularly the FOUNDATION of the ecosystems that all our corals and animals are designed around seems to be curiously unnatural/unfruitful/foolish etc.


Maybe somebody can tell me why it would ever be better to kill phytoplankton, rather then permitting it to used in the food chain, or used as a nutrient export via the skimmer?

Does it make anyone else laugh to think about a tank with a refugium and UV? Something to try to culture pods and macrofauna (which we all belive to be bennificial), and something else to try to kill any free swimming life, and delete the foundation of food for the macrofauna to thrive.

Comical

 

[NaH2O]

I'm glad you find some hobbyists' form of filtration comical...its always good to have a laugh (although I don't think its funny to bash anyone's method of reefkeeping). I don't think there is anything wrong with either natural or mechanical filtration, as long as you are aware of the pros and cons of what you choose to use. Same applies to using or not using a skimmer; having a DSB or being BB; or choosing to bind things up biologically instead of mechanically removing them...if that's what you choose to use, then great! We're here to learn about various methods, so folks can choose what they want to use and feel confident in their choices. Not to be told their methods are comical.

UV Sterilizer useage is one of the old debates. Similar to having a BB system or a DSB system debates, temperature debates, to skim or not to skim.....you see the same points from both sides time and time again. People standing by their points, and going around in circles. What's the answer?...well, its up to the individual to do some research and decide for himself/herself.

A few things about the last post. The marine food chain presented is very basic. This can be broken down even further into the microbial food web, where you'll see zooplankton feeds on more than just autotrophs. Heterotrophs are important, as well. The autotrophs are broken down into cells sizes, in which zooplankton and copepods feed on larger sized (>5µm) phytoplankton, while the smaller sized phytoplankton is cosumed by protists. Zooplankton also consumes bacterivorous protisis and herbivorous protists.

What was presented in the marine food chain, and what I briefly described is in the Ocean environment....not the closed system. There is a difference - sure these things take place in tanks, but not on the scale seen in the wild, and there may not be all species represented. I've learned from a couple of experienced people in the hobby about the closed environment, and how difficult it is to mimic the ocean in the closed system. The best we can do is keep the balance we create maintained. Something skews our house of cards, then things can go wrong, and the house of cards falls apart. In the closed system we don't have the large water volume as in the ocean. The bad can out compete the good in cases, and for some, having a UV unit is part of the check and balance they established for their system.

Some people may argue that the UV sterilizes so much, it isn't healthy for corals....taking the food source away. Well, that would have to be one heck of a UV sterilizer. I don't know if there are any that good? Don't forget light is a major food for corals (photosynthetic ones). Sure you might be taking away some filter feeder food, but you can also get rid of some nasty things, too. Some critters do need phyto....small clams for one, and some other filter feeders require dosings....but again....a hobbyist's call on their own system. Feeding a high quality food/blender mush will help to feed the little critters in a tank, as well. Fish waste, extra food, detritus and the bacteria associated with it, etc - it all plays a role in the food sources for corals and the smaller organisms. Each person must look at their own system and decide what's best for the life they are keeping (i.e. gorgonians or acroporas, etc).

I'll use my tank as an example. I've had several spawnings of tiger trochus in my system, which has led to babies being produced and grown each spawn. I find them as teeny little ones, then watch as they mature. Some I add to the display, while others I allow to continue to grow in the sump. If UV killed everything, then how could this be accomplished (along with a large skimmer), let alone the enormous pod population I have. I've also had lettuce sea slug babies hatch out and one is still living more than a year later. I keep the sleeve of my UV cleaned (routinely), and I have a 40W unit on my system. UV also oxidizes some organics. For me, the pros outweigh the cons with a UV sterilizer on my SPS system.

With regards to pods and UV sterilizers...I'll quote an older post from Adelaide of Oceanpods:

Hello - I'm not sure if all pods passing through a UV light will be done in. They actually have very good defenses to UV radiation because they end up in very exposed areas when their tide pools dry up. They have the stamina to crawl across what would be miles to a human being to get to a new pool of water. It has been demonstrated in arctic pods (think of how red Cyclopeeze is) that they can change coloration to combat the oxidation effects of UV radiation. I have recently helped out in a marine lab near my place in Santa Cruz and I placed a filter on the outflow of water which was passed through 2 sand bed filters, 3 canister filters in size ranges from 100 microns to 5 microns, and UV filter - guess what - there were still copepods coming through. We figured there was a leak in the canister filters, and the UV bulb was replaced, I believe to increase the chances of removing any remaining pods. These guys are tough!

 

[Krish]

Nice post Nikki. I think the day each individual realizes that there is more than one approach to the hobby then the better off they will be. Until you can accept that, I don't think you can be considered a true hobbyist. Just my opinion though, but what do I know...

 

[Maxx]

Luke,

Its amazing to me how vitriolic you continue to be in your posts. You seem reasonably intelligent yet your message gets lost in the over zealousness of your posts. You preach so loudly and vociferously about whatever bandwagon of the moment you happen to be on, that people actually tune out when you post.

Try something different.....

Sit back, relax, realize you are not the center of the universe and dont actually know everything there is about this hobby. Try to understand that there are many ways to do something and be successful.

Sharing information is the central purpose of this and other boards on the net. Not cramming it down peoples throats while questioning their intelligence.

Nick

 

[LakeEd]

Luke,

Its amazing to me how vitriolic you continue to be in your posts. You seem reasonably intelligent yet your message gets lost in the over zealousness of your posts. You preach so loudly and vociferously about whatever bandwagon of the moment you happen to be on, that people actually tune out when you post.

Try something different.....

Sit back, relax, realize you are not the center of the universe and dont actually know everything there is about this hobby. Try to understand that there are many ways to do something and be successful.

Sharing information is the central purpose of this and other boards on the net. Not cramming it down peoples throats while questioning their intelligence.

Nick

Nick,

VERY NICE!

 

[liveforphysics]

I applogize for being vitriolic. I often check this forum after heated technical debates from the engine design/fluid/thermodynamics forums that get me all fired up. I know I shouldnt take it out on this forum, and I am sorry. I often feel that I'm fighting a battle of Luke VS the status-quo majority, which is quite daunting at times. Its very rewarding though (at least in the engine forums) to see minds stimulated towards new approaches, try things out for themselves and go "WOW, why havn't we been doing it this way all along?"

I also agree that I get over zealous too easily. I struggle to arange/choose my words from the very abstract way that thoughts exist in my head into more concrete expressions which can be easily mulled over by all readers. With so many things in equilibriums that are unable to be appreciated/observed without useing integral calculus(purely in a qualitative relationship sence), it becomes increaseingly frustrateing to struggle for means of thought expression.

I'm sorry, and I know I dont fit in here as well as I would like. I might take a little break from posting for a while and try to practice more passive means of stateing my thoughts.

As far as the UV thing goes, I'm very glad to hear of your sucess with your tank(s?) Nikki, and I'm glad that you enjoy having a UV sterilizer. It seemed most of the basis of your reason why its not detrimental in your had to do with an inherent impotence with reguards to the throughness of the device(self-challenging any paracite fixing usefullness perhaps?). I am tempted to ask why the device remains, not personally beliveing the justification that a macrofauna population could run out of control to a detrimental degree before it was self regualted (IE, we dont see bacteria growing out of control, seems to just find the amount the system supports/needs and maintains). But again, I have no formal education in this field, and my thoughts come mainly from interpretations of my own limited observations. Which concludes UV as being something like an anti-refugium for a tank, again, just my thoughts, and I hope this brief reply is less caustic to read than many of my other posts.

sincerely
-Luke

 

[Maxx]

I often feel that I'm fighting a battle of Luke VS the status-quo majority, which is quite daunting at times.

Sit back, relax, realize you are not the center of the universe and dont actually know everything there is about this hobby.

Luke....this isnt about you. This discussion was about UV sterilizers in the home aquarium.

What status quo are you referring to? Those who enjoy reefkeeping w/o the name calling and poo flinging contests? If so, then welcome to Reef Frontiers! This board was created by two guys who hated all the hystrionics and drama of some other boards. They wanted to create a place where knowlege could be exchanged in an intelligent, rational manner. Debate is not only welcome, but encouraged by the Admin here, as long as its meaningful.

Its very rewarding though to see minds stimulated towards new approaches, try things out for themselves and go "WOW, why havn't we been doing it this way all along?"

Absolutely. So let it happen instead of forcing your narrow viewpoint onto others. Discuss, debate, think, incorporate.....

I might take a little break from posting for a while and try to practice more passive means of stateing my thoughts.

You might try avoiding stuff like this:

We could save ourselves some money and just stick a couple of nice flat pannel displays together in a box shape playing movies of the ocean.

We could get some realisticly painted platic corals that looked like something you would find in a real eco system.

We could get high-res printed photos of things that live in eco-systems and post them up around the house.

These are inflammatory and serve no purpose other than to hack someone off and instigate a fight.

I have no formal education in this field, and my thoughts come mainly from interpretations of my own limited observations.

Okay, no big deal, I'm far from being a super genius myself in this hobby. I ask questions about things I dont understand. I try to avoid making statements of fact about things I have no experiance with, knowledge of, or training in. As it is, I have no trouble looking dumb enough all on my own w/o setting myself up for more at a later date.

Okay, back to the topic at hand....

As far as the UV thing goes, I'm very glad to hear of your sucess with your tank(s?) Nikki, and I'm glad that you enjoy having a UV sterilizer. It seemed most of the basis of your reason why its not detrimental in your had to do with an inherent impotence with reguards to the throughness of the device(self-challenging any paracite fixing usefullness perhaps?). I am tempted to ask why the device remains, not personally beliveing the justification that a macrofauna population could run out of control to a detrimental degree before it was self regualted (IE, we dont see bacteria growing out of control, seems to just find the amount the system supports/needs and maintains).

Macro fauna isnt the concern here. Bacterial bloom is one thing a UV unit will help treat. In some circumstances, bacterial overpopulation, (dynoflagellates, green water, etc) can occur. UV can assist in controlling it to prevent a wipeout. Try thinking of it as a seatbelt instead of a band aid. Its there in case something bad happens, and to keep it from getting worse. Not so much to cover up a blemish or problem. Make sense?

Nick

 

[NaH2O]

The UV Sterilizer I use is on my SPS system. I have a nano (softies and small LPS) without mechanical filtration (at least until it is upgraded, then it will have a skimmer). The UV will help to lower pathogens, other irritants, and hopefully, IMO, bring system levels back down to what is seen more in the wild. An old quote from Bomber: "There are tons of things that can happen in closed systems to increase bacterial, viral, fungal levels and unfortunately most of the these happen without any warning." If I can help to eliminate some of these things, then that's great, IMO....even if it means eliminating some of the good. As I said before, for my SPS system, the livestock and water quality I am trying to achieve, the pros out weigh the cons. That is why I say it is up to the individual.

Its very rewarding though (at least in the engine forums) to see minds stimulated towards new approaches, try things out for themselves and go "WOW, why havn't we been doing it this way all along?"

One thing to keep in mind. What you think is a new approach, may not be a new approach, but one that had been used for a long time...maybe ages ago. It might have been phased out for a number of reasons (i.e. advancement in technology, increased knowledge, etc). Coming up with new ideas, or even using old ways is fine, as long as you appreciate where others are coming from. Debate is fine, as long as it doesn't turn into flame throwing. We are here to learn, and not to say "my tank is run the best...see everything is alive, and you're stupid to do it any other way". It's a matter of understanding what you want to keep, and learning methods to give the livestock the best environment for their needs. This way your inhabitants are not only surviving...but thriving. I wouldn't use a UV sterilizer on a system set up for a bunch of filter feeders, but I would use it on an SPS system. Others might disagree, and that's fine. Some others might even say, why use a UV when there's ozone? (and I have reasons for not using ozone). The UV debate is an old one.