Water Changes

[Meyer Jordan]

OK. Just for you Randy.
If a pond is correctly designed, installed and maintained, then no, aeration is not needed. If a pond is large enough to where the wind fetch is sufficient, then no, aeration is not needed.
As with any water quality issue regarding a pond, the source of that issue can usually be found in an imbalance between fish load and biofiltration/flow rate.
Aeration is required or desired usually because of pond design flaws or aesthethics, i.e. Pea Soup (which incidentally is desired in a Fishery pond)
The discussion of aeration pro and con has the potential to be quite lengthy. That is why I suggested a new thread to discuss 'contraptions'.
Asking morewater about the scale of microscopy is hoping for a quick answer, not a lengthy discussion.

 

[Mucky_Waters]

OK. Just for you Randy.
If a pond is correctly designed, installed and maintained, then no, aeration is not needed. If a pond is large enough to where the wind fetch is sufficient, then no, aeration is not needed.
As with any water quality issue regarding a pond, the source of that issue can usually be found in an imbalance between fish load and biofiltration/flow rate.
Aeration is required or desired usually because of pond design flaws or aesthethics, i.e. Pea Soup (which incidentally is desired in a Fishery pond)
The discussion of aeration pro and con has the potential to be quite lengthy. That is why I suggested a new thread to discuss 'contraptions'.
.

Good answer. But I believe there is more to be said about aerators and the size of ponds, perhaps we can continue discussing it over in this thread.

 

[morewater]

How does that relate to the cellular scale?

Electron micrographs (transmission or scanning) are relatively useless without an indication of scale (either in micrometers of Angstroms). This particular one does not, and as the image is of a sterile sample (there are no organisms with which to guesstimate the scale,) any answer that you come up with will be just as accurate as any that I can come up with.

I merely pointed out that it's an SEM micrograph of a subject that was sputter-coated with gold. This image is a negative-negative-image with the image gathered from backscattered electrons. As an aside, I'd guess that the accelerating voltage for the electrons was somewhere in the 25-30KV range and given the resolution of the image, I'd hazard to say that the filament of choice was lanthium hexaboride (LaB6) rather than tungsten. I couldn't hazard a guess on the make of the SEM, be it a Jeol, Philips or Hitachi.

SEMs are generally used in the materials sciences field (sometimes in a Hospital setting, but that's a novelty), TEM's are the workhorses of the pathology field.

Fair warning. Don't put an SEM in your pond. They're big, heavy and bulky and will displace the water in your pond. You will have effectively committed yourself to a water change while at the same time destroying an expensive piece of electronic equipment. There, I justified this post by incorporating the term "water changes".

 

[MitchM]

Came across something that may be an argument FOR water changes.
I haven't read through and completely understood it yet, but I will be doing that.

Redox values can diminish over time and water changes can keep the redox value high.

http://www.americanaquariumproducts.com/Redox_Potential.html

UV sterilization can keep redox values high in place of water changes.

http://www.americanaquariumproducts.com/AquariumUVSterilization.html

If anyone else has any thoughts on redox and water changes or UV and redox, please share.


.

 

[Meyer Jordan]

Neither of these articles are peer-reviewed. Some of the logic used is 'fuzzy' to say the least. None of the links are to scientific articles.
Most importantly, both articles specifically target Aquaria. Water changes are considered required to maintain overall water quality in this form of aquatic habitat. Outdoor Garden Ponds exist in a completely different overall environment and are not subject to the same limitations that constrict aquarium water quality balance. Minerals are constantly being replaced by simple atmospheric precipitation (dust, etc.), organic litter (leaf drop, dying organisms, etc.) and by liquid precipitation.
Redox is any form of oxidation, whether it be Nitrite conversion or a rusting pipe. Because most Garden Ponds maintain a fairly high level of DOM, Redox will also remain high.
These articles have very little, if any, application to ponds.

 

[Mucky_Waters]

. both articles specifically target Aquaria. Water changes are considered required to maintain overall water quality in this form of aquatic habitat. Outdoor Garden Ponds exist in a completely different overall environment and are not subject to the same limitations that constrict aquarium water quality balance. Minerals are constantly being replaced by simple atmospheric precipitation (dust, etc.), organic litter (leaf drop, dying organisms, etc.) and by liquid precipitation.
Redox is any form of oxidation, whether it be Nitrite conversion or a rusting pipe. Because most Garden Ponds maintain a fairly high level of DOM, Redox will also remain high.
These articles have very little, if any, application to ponds.

Meyers, I can't speak to the logic or scientific validity of the article, but the logic that water changes are definitely required in aquariums but definitely not in outdoor ponds seems a little fuzzy to me. lol
After all, many backyard ponds are really not much more than aquariums sitting outside. Sure they may not be made of glass, and they may be buried in the ground, but the same processes that go on inside are still going on outside. It's true that some ponds may greatly benefit from natural rain as a substitute for water changes, but some may not and, in fact, may suffer from evaporation rates that far exceed those found indoors.
I see that you are from Pensacola Florida where the average annual precipitation is 61.2 inches. Where I live the annual precipitation is only around 13. 5 inches, with most of that happening as snowfall or rain in the winter time. During the summer here when it's very hot and little rain evaporation rates can be ridiculously high and are a very real problem. And since I already start with relatively hard well water my pond water would quickly exceed healthy GH levels if all I did was top up my pond rather then do some sort of water changes like I do. As it is I already get an obvious ring of mineral deposits in my pond at the high water level mark in the summer time despite the fact that I maintain a constant trickle water change system.
At best I think a person could argue that water changes may not be as beneficial or necessary in some outdoor ponds as they are in indoor aquariums, but the individual circumstances, the geographical location of each pond, and the specific water qualities parameters you wish to maintain will really be the deciding factor whether to do water changes or not. But of course as you have pointed out many times, a person could be doing more harm then good if water changes are preformed incorrectly.

 

[Meyer Jordan]

Meyers, I can't speak to the logic or scientific validity of the article, but the logic that water changes are definitely required in aquariums but definitely not in outdoor ponds seems a little fuzzy to me. lol
After all, many backyard ponds are really not much more than aquariums sitting outside. Sure they may not be made of glass, and they may be buried in the ground, but the same processes that go on inside are still going on outside. It's true that some ponds may greatly benefit from natural rain as a substitute for water changes, but some may not and, in fact, may suffer from evaporation rates that far exceed those found indoors.
I see that you are from Pensacola Florida where the average annual precipitation is 61.2 inches. Where I live the annual precipitation is only around 13. 5 inches, with most of that happening as snowfall or rain in the winter time. During the summer here when it's very hot and little rain evaporation rates can be ridiculously high and are a very real problem. And since I already start with relatively hard well water my pond water would quickly exceed healthy GH levels if all I did was top up my pond rather then do some sort of water changes like I do. As it is I already get an obvious ring of mineral deposits in my pond at the high water level mark in the summer time despite the fact that I maintain a constant trickle water change system.
At best I think a person could argue that water changes may not be as beneficial or necessary in some outdoor ponds as they are in indoor aquariums, but the individual circumstances, the geographical location of each pond, and the specific water qualities parameters you wish to maintain will really be the deciding factor whether to do water changes or not. But of course as you have pointed out many times, a person could be doing more harm then good if water changes are preformed incorrectly.

A good point. Of course there are exceptions to most rules. As to your point on effects of Hard water and high evaporation in garden ponds, my question would be--How do the natural ponds and lakes in your area respond to this?

Aside from that, generally speaking, trace minerals are constantly being replaced in the vast majority of Garden ponds by the processes that I earlier described. Redox levels are maintained. Let me point out that this may not include dedicated Koi ponds that apparently strive to exclude any natural processes other than Nitrification to insure visual perfection. Dedicated Koi ponds and indoor aquaria are quite similar in operation and purpose.

 

[Mucky_Waters]

A good point. Of course there are exceptions to most rules. As to your point on effects of Hard water and high evaporation in garden ponds, my question would be--How do the natural ponds and lakes in your area respond to this?

Most of the local lakes and ponds are flow through systems, but there are a few lakes (large ponds?) that suffer from high mineral concentrations that leave them totally uninhabitable to fish life.
Spotted Lake & Mahoney Lake are a couple of the more well-known ones. Some of the smaller, shallower "lakes" like White lake, dry up completely in the summer time and all that is left is a crust of white mineral deposits where the water use to be.

Spotted lake

Mahoney Lake

White Lake

 

[Meyer Jordan]

Now that is HARD WATER!
Spotted Lake is quite pretty. Do you know what causes the spotted effect?
What part of B.C. do your live in?

 

[MitchM]

Our natural lakes and ponds around here will get their minerals from surface runoff.

I'm not quite following the logic behind how our ponds and aquariums are so different. I've tested rainwater before and GH comes up as zero.

The articles I posted may not be peer reviewed, and they are from a manufacturer of certain products, so they may not be up to the standard of peer reviewed articles, but I'm interested in whether the concept is valid.

The article mentions that calcium (Ca2+) and magnesium (Mg2+) may still register on GH test results, but have lost an electron, so are no longer available as reducers.

How does a high level of DOM affect redox?

I'm interested as well as how UV sterilization affects redox.

.

 

[Mucky_Waters]

Now that is HARD WATER!
Spotted Lake is quite pretty. Do you know what causes the spotted effect?
What part of B.C. do your live in?

I don't really know (or if anybody knows) what causes that spotted effect on the lake, or why other similar mineral lakes like that don't have the spots, but it is a kind of cool phenomena.
I live in a tiny little community called Olalla. If you zoom out on this >Map< you'll see where that is in relation to the rest of BC.

 

[Meyer Jordan]

Which are we discussing here? Redox or GH? These are separate things.

REDOX=oxidation-reduction=a chemical reaction between two substances in which one substance is oxidized and the other reduced.
DOM=Dissolved Organic Matter=Dissolved Organic Carbon=In general, organic carbon compounds are a result of decomposition processes from dead organic matter such as plants or marine organisms.

In order to have a high DOM level, decomposition (oxidation) must occur also on a high level. This high level of oxidation equates to a high level of REDOX. There is certainly no shortage of organic matter in a typical Garden Pond.

As regards GH-
"Calcium is an important component of plant cell walls and the shells and bones of many aquatic organisms, while magnesium is an essential nutrient for plants and a component of the chlorophyll cycle. Waters with calcium levels of 10 ppm or less are usually oligotrophic, supporting only sparse plant and animal life. Eutrophic waters typically have calcium levels above 25 ppm."
Exploring the Environment--Water Quality

From this definition it can be deduced that if a body of water supports plant life then calcium levels must exceed 25 ppm and magnesium is also in sufficient quantity.

 

[pecan]

Mucky, where I live our average rain fall is 10" per year. with a long stretch in the summer that stays above 90 degrees and into the low 100's. Most water comes from snow melt in the mountains. Very interesting post that I can relate to.

Meyers, I can't speak to the logic or scientific validity of the article, but the logic that water changes are definitely required in aquariums but definitely not in outdoor ponds seems a little fuzzy to me. lol
After all, many backyard ponds are really not much more than aquariums sitting outside. Sure they may not be made of glass, and they may be buried in the ground, but the same processes that go on inside are still going on outside. It's true that some ponds may greatly benefit from natural rain as a substitute for water changes, but some may not and, in fact, may suffer from evaporation rates that far exceed those found indoors.
I see that you are from Pensacola Florida where the average annual precipitation is 61.2 inches. Where I live the annual precipitation is only around 13. 5 inches, with most of that happening as snowfall or rain in the winter time. During the summer here when it's very hot and little rain evaporation rates can be ridiculously high and are a very real problem. And since I already start with relatively hard well water my pond water would quickly exceed healthy GH levels if all I did was top up my pond rather then do some sort of water changes like I do. As it is I already get an obvious ring of mineral deposits in my pond at the high water level mark in the summer time despite the fact that I maintain a constant trickle water change system.
At best I think a person could argue that water changes may not be as beneficial or necessary in some outdoor ponds as they are in indoor aquariums, but the individual circumstances, the geographical location of each pond, and the specific water qualities parameters you wish to maintain will really be the deciding factor whether to do water changes or not. But of course as you have pointed out many times, a person could be doing more harm then good if water changes are preformed incorrectly.

 

[MitchM]

Which are we discussing here? Redox or GH? These are separate things......

I brought up GH because I thought redox is a combination of reducers and oxidizers.
Redox measurement (by the use of an ORP probe) seems to be a more important value than PH.

.

 

[Meyer Jordan]

I prefer to use BOD and COD measurements. The results are basically the same as a REDOX measurement as Oxygen is used in any oxidation process and the results are in a form that can be immediately related to water quality.

ORP measurements are not always that accurate because of the many influencing variables.
This from Wikipedia-
"Although measurement of the reduction potential in aqueous solutions is relatively straightforward, many factors limit its interpretation, such as effects of solution temperature and pH, irreversible reactions, slow electrode kinetics, non-equilibrium, presence of multiple redox couples, electrode poisoning, small exchange currents and inert redox couples. Consequently, practical measurements seldom correlate with calculated values. Nevertheless, reduction potential measurement has proven useful as an analytical tool in monitoring changes in a system rather than determining their absolute value (e.g. process control and titrations)."