Pond Boss Forums GENERAL QUESTIONS Water chemistry Universal Solvent Article Correction

To all POnd bosss subscribers,
Just scanned the new POnd Boss and just wanted to corect something b/f it confused some folks. Bob you mentioned the pH on warm summer day maybe 8.2 then drop to 6.5 by the afternoon. You meant it to read the other way around I assume. THe diel fluctation of pH is that pH is increased throughout the day as dissolved oxygen increases, and is at its lowest point from CO2 (respiration) just prior to sunup. This fluctation is lessened when alkalinity is above 20 ppm.

Also a possible correction I noticed but nothing major....I think I remember reading that neutral pH is 7, but thats only for water the temperature of 25 degrees Celcius. And just to add some flare...most people think pH only ranges from 1 to 14...not so. pH can actually be recorded at -1 and 15 at different temperatures.

tritonvt - so what are you saying that neutral pH is at water temps of 33F and 96F?

Bill that's your 666th post...scary!

Anyways what I meant was if you have a water temperature of 77F the pH of neutral water will be 7. However, if you have a water temperature of 59F then the pH of neutral water will be 7.2. Likewise if you had a temperature of 86F then the pH of neutral water will be 6.9

The only reason I posted this was just to bring some more in-depth look at the chemistry in ponds. (I really liked the article in PB) Also it brought me to a new question....

When Bob said that a pH of 6.2 and 9.0 are the most productive for fish, I wondered if this fact would be taken into account?

I really doubt it, seeing that the pH of neutral water never changes more than a couple tenths and most of your fish production will be done at higher temperatures which would correspond to the ideal '7' pH.

Chris

Chris the 6.2-9.0 is pretty general in nature. I don't think the change in temperature would make alot of diff. Instead of a general article on water chemistry how about an article on each of the important parameters. Heck this same type think has been said over the years many times in the magazine. I was quoted about alkalinity in the magazine back in I think 1999. Bob, would the readers not be better served to dive into detail in a separate article about each parameter, whatcha think?

One other thought Chris, I look at the dissolved oxygen percent saturation on my YSI to help in determinations of phytoplankton abundance. The compensation for temperature is a big part of this calculation. What I'm saying is good point!

There will be a correction in Jan/Feb for the pH boo-boo in the water article.
Regarding each parameter, I have had no trouble finding plenty of information. The struggle comes when trying to interpret the interrelationships when several parameters come into play. Remember, Pond Boss essentially exists to help individual landowners improve ponds and lakes.
So, water quality and chemistry can get quite confusing.
I think a series of articles describing each important parameter will be worthwhile. I'll think about how to do it where readers can actually use the information.
Where it gets ticklish is trying to figure out how a given pH is a response to a given alkalinity, which is directly influenced by particular minerals, but how different metals and minerals influence pH, but not necessarily alkalinity. Then, throw in some other facts like dissolved solids and particulate matter, influenced by minute by minute biological functions of plants, bugs, plankton, animals.
So, we pin down a few basic parameters...pH, alkalinity, temperature, oxygen....to do the best we can to manage a pond and its inhabitants.
So, if you guys have some specific ideas about articles regarding water chemistry that would help Pond Boss readers, I would entertain your thoughts.
Also, I selected pH of 6.2-9.0 because most fish can still reproduce within those bounds. Most fish can certainly live outside those pH bounds, but reproduction, and survival of young diminishes.