UV light recommendations

[Meyer Jordan]

As @Mitakuye stated, 'Patience' is key. Nature will move at its own pace, but if the natural food chain is allowed to develop, then any excess algae issues will abate.

 

[Mucky_Waters]

That's what I thought, Meyer. Why would people treat a symptom rather than the cause? Sounds like our health care in this country.

Actually proper medical care should try and treat the symptom and the cause, but in many cases it is only possible to treat the symptom. For instance if you were skateboarding and fall and break your arm your health care provider (doctor) is only likely to treat your symptom (the broken arm), and leave the cause (skateboading) up to you.
In the case of trying to treat a pond with green water (free floating algae) there are many factors involved that could cause an outbreak. Overfeeding is only one and I don't believe it is the most common problem. You can, and most likely will, get green water in a brand new pond with no fish at all. Even swimming pools get green water algae outbreaks, which are generally controlled with chemicals. Often it is new ponds that suffer worst from green water, before the other types of non free floating algae have had a chance to establish themselves. This is often referred to as "New Pond Syndrome". This is why the advice is often given to be patient and just allow your pond to balance. However, there is nothing wrong with running a UV light to help clear up the green water until the other types of algae have had a chance to establish themselves or until you've taken other measures to clear it up.
In my case I usually only get green water in early spring as soon as the water starts to warm up probably due to the dead algae from the previous year starting to break down . Yes it would clear up on it's own accord, but by flipping a switch and turning on the UV light at the first sign of greening water I can avoid the whole cycle.You can think of it as a preventative measure, like taking extra vitamin C and zinc at the first sign of a cold instead of ignoring the "symptoms" and taking all kinds of cold medicines after you are really sick. Except the UV really WORKS!

 

[Meyer Jordan]

Except the UV really WORKS!

Where does the nutrients released by the decaying dead algae go? And what then feeds the zooplankton?

 

[Mucky_Waters]

Where does the nutrients released by the decaying dead algae go?

Some of it remains in the water, some is absorbed by the emerging plants and non free floating algae, and hopefully if I'm doing my part, much of it mechanically filtered out.

And what feeds the zooplankton

I'm sure you know the answer to that already, but if not maybe this will help.

 

[Meyer Jordan]

Some of it remains in the water, some is absorbed by the emerging plants and non free floating algae, and hopefully if I'm doing my part, much of it mechanically filtered out.

I'm sure you know the answer to that already, but if not maybe this will help.

Excellent video. At 3:00 to 3:10 the question is answered: that zooplankton feed on phytoplankton. Since a UV kills this phytoplankton there is no source of food to establish a community of zooplankton, thereby interrupting the natural food web.

As far as floating algae is concerned, I would not particularly want any of this since the vast majority of species are blue-green algae which are known to be quite toxic.

 

[sissy]

thing is quick fixes can kill

 

[Mitakuye]

thing is quick fixes can kill

Yes, as a result of mistakes. This is why exact directions must be followed. Most do not want to

Lets not forget that tremendous fish kills do naturally occur, as a result of phytoplankton collapse, due to intense surges of warm water deep in the ocean creating huge blooms which inevitably ends. Same occurs in lakes when nutrient heavy water drains into the lake. Although major fish kills are a problem for fisherman, biological collapse events feed the ecosystem's diversity. Circle of life.

 

[Mitakuye]

There are toxic algaes, but these often have to be introduced into the waters and require specific environments rather than simply appearing. This is one reason why boats are required to be thoroughly washed before going into different bodies of water.

UV's have two purposes, disinfect (also called clarify) or sanitize. Disinfect means to simply reduce organism population, rather than outright removing so this alters the balance thus resulting in more macroalgae growth and more time, money, and maintenance to remove the macroalgae. Macroalgae also feeds fish and creates a protective area for fry.

 

[Mitakuye]

I am not for sure how to explain this, but going to try.

Ultimate goal should be to displace nutrients. This is done by a constant cycling of water or flora growth which is then removed or phytoplankton to feed fish growth and the fish are eventually "removed".

Reason phytoplankton are used in pond aquaculture is due to being a very cheap food source, but then these fish are constantly absorbing the nutrients from the primary producers, fish are spawning, and fish are removed via harvest.

If UV devices are used, then more intervention is involved due to removal of the nutrients, either by removing macroalgae and/or pruning flora and/or other techniques.

 

[Mitakuye]

To use or not to use UVs depends on the operator's desire, how they want to manage their pond and the aesthetics of the pond.

Just be aware, more intervention involved then the more maintenance involved, but the nutrients have to be reduced by either dilution or displacement.

 

[Mitakuye]

Also, there is always "excess" nutrients for something to grow in the water.

As to "what will grow", depends on how the system is managed.

 

[Mitakuye]

In being fair and objective, this is a complicated subject, with no specific end.

If there is a desire to use an UV device, then I like these brands for smaller systems.

http://pentairaes.com/emperor-aquatics-hobbyist-1
http://www.evolutionaqua.com/acatalog/evoUV.html
http://www.koiponduv.com/wlim_wave_uv.php

 

[Mitakuye]

Take a look at the American Aquarium web site and take a look at their article on UV lights. It explains why they are all not the same. Also watch the video

I suspect this is a relatively virgin pond due to how clean the liner is at the water fall's head. I bet this pond owner also employs macroalgae control as well, because, since he kills much of the phytoplankton, the nutrients have to go somewhere and the flora density is severely lacking. I figure macroalgae control might be another video he submits.

 

[Tula]

To use or not to use UVs depends on the operator's desire, how they want to manage their pond and the aesthetics of the pond.

Just be aware, more intervention involved then the more maintenance involved, but the nutrients have to be reduced by either dilution or displacement.

I use a UV and freely admit my pond is higher maintenance, but I enjoy caring for my pond, and look forward to it all winter.

 

[Meyer Jordan]

There are toxic algaes, but these often have to be introduced into the waters and require specific environments rather than simply appearing.

Cyanobacteria are easily introduced to body of water by wildlife transfer, most notably aquatic fowl and there are species of cyanobacteria that will grow in most any environment.
What @tbendl has often referred to as 'Pond Snot' is quite likely a cyanobacteria (bluegreen algae)