Pond Boss Forums INTRO Questions & Observations affordable DO meter?

So I need to purchase a DO meter, and all of the ones I've found online seem to start at $250 or more, without the probe which usually is another $250 or more. Does anyone know of a DO meter that doesn't cost quite so much but is still a good meter?

This is a question I've asked previously too Walt. Cecil mentioned something about DO meter that wasn't too expensive. Perhaps he'll wade in.

Paging Cecil?

LaMotte sells test kits for less than $50 if you want to go less expensive.
Richmond Mill Lake just bought a YSI DO200 for something like $250, complete with probe. Be sure to specify Fahrenheit instead of Centigrade for the thermometer. I don't remember where the bought it but it was a good deal and they are pleased with it.

The YSI sounds like a winner to me. I'll look for it online. Thanks, Bob!

walt got three of the ysi do200 they do nto holdup for us. I have had them back to Aquatic Eco couple of times. I got them on clerance at BPS for cheap so worht it but not if buying for $240+$ for probe. Best to pony up and get the ysi 55 for $664. I have used it weekly/daily for 5 years. Or test kit for now.

Greg, do you or anyone else have any experience with or knowledge of any of these:

http://www.eseasongear.com/milwaukeesm600.html

http://www.instrumart.com/Product.aspx?ProductID=23681

http://www.mbhes.com/dissolved_o2.htm

The Hannah product doesn't have a price listed but the other two are much less expensive than the YSI and most other brands I found online. I'd like to have a real meter as opposed to a test kit, but my income is pretty sparse at the moment; I couldn't for instance buy the YSI 55 even if I wanted to.

What Bob said. Guys do some of you really really need a D.O. meter? I raise fish in four ponds and hardly ever use mine. Used to use it when hauling fish (which I absolutely hate doing), but now if the aerator is running and I don't overload the tank there is no point in checking. If the aerator goes out is the D.O. meter going to make a difference? Heck no! If oxygen production stops there is no point in getting a reading! That's why I have oxygen back up if the aerator fails. Or some folks use oxygen and use the aerator as back up, or use both.

Same goes for a pond. If you have an impending fish kill and know the signs of an impending fish kill you'll know you going to have problems before the D.O. actually gets in the serious zone. (Algae bloom crashing and turning brown, Clarity due to an algae bloom less than 12 inches, odor in the water, fish off feed etc.) And if you have a fish kill your D.O. meter isn't going help you.

If you are a good pond manager, don't overload your ponds as in fish production ponds vs. recreational ponds, mix your water column with a diffuser in the summer you should never have to worry about a fish kill due to a turn over or low D.O, or have to take D.O. measurements. And for those of you in the north if you keep some water open during ice up or keep snow of then again you shouldn't have to worry about low D.O. then either. Yes there are exceptions but 99 percent of the time fish kills are the pond owner's fault and are completely preventable. Ignorance has killed a lot of fish. Been there done that.

For the amount of money you pay for a good meter you could spend just a little more and buy a LaMotte test and a surface aerator for an emergency!

I paid over $700.00 for one and I can honestly tell you if I had to do it over I would just go with the LaMotte test Bob suggests. (I actually have a LaMotte test to calibrate the meter!) I actually trust the LaMotte test over the D.O. meter! This winter I doubled checked my D.O. with my LaMotte test just to be sure I wasn't getting a weird reading.

And here's another thing to keep in mind: I have a PHD in aquaculture down the road from me that raises thousands of dollars worth of hybrid striped bass in an recirculating aquaculture system. Guess what? He only uses the LaMotte or Hach test kits to keep track of water quality parameters. Says he doesn't trust meters. Apparently he's had a bad experience with one.

Look I know there are good reasons to have a meter (such as quicker readings of the water column without the need for a water capture system), but isn't it true in some cases we think we need a pricey gadget when we don't need it? You know, "The difference between men and boys is the toys for men are more expensive."

This is my two cents. Take it or leave it.

Ttruthfully, Cecil, I was right there with you - felt I didn't need one. Then a week ago a hatchery guy was standing on the bank of a half-acre pond he had brought me 20 tiger bass to stock into, and he threw his DO meter probe out into the water and it came back under 1ppm. I had had no idea previously the pond had low oxygen; it's full of small bluegill. Granted I did treat it a month ago for watermeal, so it's possible that the dying watermeal is taking up some of the oxygen, but I wouldn't think it would take that much a month after treatment?

There's another pond (phosphate pit) on the same property, this one close to two acres, that had the same problem - under 1ppm. It, too, was treated a month ago for watermeal. It's completely clear now, but was covered from one end to the other before treatment.

Both of these ponds have a lot of trees all the way around them, and both are off in holes, especially the first one. They've both been very exceptional ponds in years past; a 1.75 pound bluegill was caught from the larger pond a little over twenty years ago, with no management whatsoever. The owner ruled out months ago spending the money to get aerators, and I don't have anywhere close to that kind of money myself, as the ponds are a good ways from a power source and the aerators would have to be windmill or solar-powered. I've asked the owner if it would be possible to get one bank of each pond cleared of trees with the thought that the added wind action might help.

Could clearing a bank make a significant difference?

I should add that there are two other pits on the same property that had normal DO levels, one at 5.5ppm and the other at 6. The one that had 5.5 was treated about two months ago for watermeal, though it was never more than about 20% covered with the weed prior to treatment; the other pond never had watermeal. Both ponds have fewer trees around the banks than the two with DO problems.

Yes but IMHO if the D.O. is that low much more needs to be done as in what you mentioned above.

Keep in mind there are circumstances where a D.O. meter is good to have but for most pond meisters I personally believe the money could be spend on something else.

Not many fish live at 1 ppm. Not many ponds have 1 ppm water without some serious problem. If there were live fish in those ponds then my guess is the meter was wrong or the operator made an error.

walt did you stock fish in those? If so they are dead OR you proofed Cecil's point a meter can be wrong. Seriously 1 ppm is bad news rarely do we see that, something strange to cause issues like that killing watermeal will not do this alone.

If you put fish in that they should have instantly came to surface. i have doen it only once, it was like the water was on fire grass carp were jumping out of the water.

Cecil,

I just had this happen to me. The algea turning brown all of a sudden? What can I or should I do to help this situation? I can't aerate at this point unless I am out there doing it with a motor of some sort? My water looks fine still but all my weeds are bronw and the algae too. Just out of nowhere?


RC

Greg, we didn't stock in one of them; when we were standing on the bank of the other one, as the hatchery guy was staring at the meter ominously, I asked him more than once if we should put those bass in another pond instead. But I have this broken part of my brain that sometimes allows me to do really, really dumb stuff even though I fully realize while I'm doing it that it is really, really dumb (probably a hangover from my first three years of undergrad, pun intended). So for some inexplicable reason he released the 20 bass into the half-acre pond, and they did indeed immediately start coming up to the surface for air.

I went back the day after that and the day after that to look for floaters or ones that had washed up on the bank, and didn't see any; I know it's very possible they just sank, or got eaten by a raccoon/possum/turtle/etc.

But when we got to the second pond with low DO, thankfully I was able to summon enough intelligence to not hesitate to tell him we would just stock those in the pond with the 6ppm, which is horrendously overpopulated with the most stunted bluegill I've ever seen anyway so the LMB are having a big party in there right about now I would say.

Both of these ponds have steep banks all around them, and heavy growth of trees all along the bank; they're both old pits over 70 years old, and both have muck bottoms; I just today noticed that the larger pond has a good bit of leaves built up on the bottom. Could all of that combined with a very heavy blanket of watermeal dying, combine to cause DO levels that low? If it's still not probable, any ideas what could be causing it? Both ponds have had great fishing in years past, but they've both been covered with watermeal for several years now and the landowner had just given up on them.

I wonder if he even moved the meter back and forth or it was calibrated.

Filamentous algae or phytoplankton?

The fact that the fish came to the surface immediately in the one pond with low DO (according to the meter) in which we released some, makes me think it probably really was low. Any thoughts on what could cause it to be that low?

Heavy WM or DW infestations that have been killed can use up all the O2. They typically have low DO to start with for several reasons including that the WM/DW prevents plankton and other plants from adding O2.

Thanks, Eric! That's encouraging to hear. I knew that watermeal often causes fish kills in ponds it's been in a while, and the lack of plankton and resulting low DO makes perfect sense as the explanation. As much watermeal as there was covering these two ponds, I guess that could be a lot of oxygen being taken up by the decay.

What's the time frame I should expect as far as the DO beginning to get back closer to normal, fish-supporting levels? Do you think I should remove the trees from one bank of each pond to facilitate wind movement across the pond?

Walt, Kelly Duffie, when he was THE water and pond chemical guy with Estes Chemical, once posted a picture of himself spraying a DW covered pond. He said that it was impossible for fish to live in the heavy concentration. This stuff reproduces at high speed and is tough to totally eliminate without multiple chemical applications. Greg once told me about just how often (daily as I recall) it reproduced. I would bet my money that was the problem.

Your mention of doing incredibly dumb stuff hits pretty close to home. What was I thinking?

I doubt that I would cut the tree(s). I don't think it would do that much good. However, it might help in some small way. Sunshine is a pretty good DO generator.

Walt that is a personal choice depending on the location and owners. I might clear some brush but not cut many trees. I would do nothing until the WM was gone. It often takes several attempts as it reestablishes from seeds in the bottom mud that float up when sunlight penetrates.