I've been reading about aeration and shutting the pump after the fall overturn and re-starting it in spring before the bottom waters drop below 3 ppm DO levels. Well my pond is over 20 feet deep and the thermocline forms at over 10 feet, so what's a convenient way to sample bottom water. Also who makes or sells analytical kits for DO testing. It would be interesting to test through the seasons and see the variations in DO. And also judge the effectiveness of the aeration system and bubbler placement.

Call our office (800)687-6075, ask Kathy to send you a sample of Pond Boss magazine (go ahead and subscribe while you're at it). Inside the magazine are several advertisers who sell all kinds of water testing equipment. In order to collect a sample from bottom water, you will need a special device lowered with a cord. Or, you can buy a meter which measures temperature and/or oxygen, and the cable can be lowered into the lake to different depths. You can learn a lot from that data.

Actualy I did subscribe, and you sent me 2 issues already. Great and informative magazine, between this forum and the articles in the magazines I'll save alot of wasted efforts in my pond management. Didn't see any advertisers for bottom sampling devices. If I remember back (way back) from my college days they were called Nansen bottles and Van Duren bottles (2 different types) I'd much prefer them because a sample of bottom water can be tested for pH, nitrate, TDS, and many more parameters as well as O2. A probe will only read O2 and I'll have no water to play with. Any idea where I can get these bottles, or whatever they may call the bottles these days?

PaPond, check this link, the mason jar idea looks simple enough.

Sampling jar

PaPond -- Wildlife Supply Company (Wildco) has those pieces of equipment that you mentioned. I'll post their website below. However, the prices are not low!

http://www.wildco.com/

Dave

thanks Dave, but you're right they are pricey, I think I'll try the mason jar that Wood suggested, looks simple and effective. Plus it leaves alot of extra cash for test kits. Now I can even spring for the phosphate test.

have either of you had experience testing bottom waters for DO or nutrients? any suggestions?

PaPond, sorry I'll have to leave that to someone that has actually done these tests. I just like finding things.

Check with companies like Cole-Parmer or Forestry Supply for a sampler; however you can easily make your own from PVC pipe. Attach two ball valves together, separated by a section of PVC pipe appropriate for the size of sample you need; make sure the ball valve handles are aligned and open / close in the same direction. You want the handle to open towards the bottom of the sampler ( I'll explain why in a second). Next, attach a length of PVC pipe to the upper ball valve suitable for the depth you want to reach. Attach a rope or cable to both ball valve handles, so that they can be closed at the same time. With the valves about 75% open, lower the device to the desired depth, close both valves with the rope, and you now have a sample that contains only water from the zone between the two ball valves.

PaPond = based on your original post, I assumed that you wanted to monitor dissolved oxygen (which is a good idea).

Hach Chemical makes a multitude of water quality meters, and they also have simple test kits where you use chemicals, count drops, and watch for a color change. They actually are quite reliable tests. For example, I looked up their dissolved oxygen test kits, and you can do 100 tests from a $48 test kit. I tried to paste the web address for that test kit, but the string was lines and lines long. Perhaps go to their web site, address below, and search for "Dissolved Oxygen, Model OX-2P, 100 tests, Drop Count."

http://www.hach.com/

As for other water quality tests that you might want to consider, let's see if Bob Lusk spots this and answers that question. You certainly can test for nutrients (Hach makes a huge array of test kits, including kits for a number of common water quality measurements), but I'm wondering why? Are you concerned that nutrients are too low or too high?

Dave

Dave
Thanks for your reply, I'm kind of partial to Chemetrics ampules as I have one of their colorimeters and they're quite accurate. I was hoping you could suggest what parameters are usually monitored in terms of nutrients and possibly chlorophylls. Why do I want to test, I'm a chemist, almost retired, so it's what I do, test and fish. Life is good!

OK, PA!! :-) That's one of the "problems" with this forum -- you never know to whom you are talking. You probably know more about water chemistry than me! This is not my expertise (directly), so I got some advice from our limnologist to try and provide a decent answer. He suggested chlorophyll a, pH, total phosphorous, soluble reactive phosphorous (meaning the biologically available amount), and total nitrogen.

Again -- hope this helps!!

Dave

PaPond, you are a scuba diver, why not sample that way?

I am a scuba diver, and I have dove in my pond, and you are correct I could sample by simply opening a bottle while down there but it's not exactly a tropical wonderland down there either. Besides I'm adding aeration and would like to be able to monitor the DO levels frequently, including in the winter. So a bottle on a string is much more appealing.

PaPond - As a chemist, you probably know when you are sampling for DO you do not want to "bubble" water into a sampling jar/bottle. The sampling jar that "Wood" referenced seems like a pretty good device for collecting water without bubbling at discrete depths and with minimal exposure to air considering it is homemade. FPLover's sampler is also a good idea for capturing water without bubbling/air exosure. But I'm not sure how you fill a test bottle with his sampler without pouring/splashing. Could add a hose to one of the ball valves.

For all non-oxygen sampling I use a modified old large glass acid bottle with a finger handle. I made a base weight the diameter of the acid bottle base out of lead (you could use cement). I then duct taped it to the bottom of the bottle. Wrapped tape across the lead bottom and up each side of bottle. Then wrap tape around the perimeter of the bottle to keep the side tapes from coming off. I tie a rope to the finger hole. I use a one hole rubber stopper with an eye screw in the hole. Tie a string to the eye screw. Lower the stoppered bottle to desired depth and pull string/cork to fill bottle with water. This works fine for all tests except DO.

I have another home-made smaller sample bottle which would be better for sampling thru ice because you would not need as large of ice hole to drop bottle thru. I took a 16 oz glass pop bottle and duck taped a very large U bolt to it so the bottle was between the U bolt. U bolt was heavy enough to sink the bottle. I wraped copper wire around the bottle neck and made a loop to attach a narrow rope. My small sample bottle is not corked, but it could be, just like the larger sampler above. I spent the "big dollars" for a DO YSI probe. I have seen used YSI DO meters reasonably priced on ebay.

I would not spend the time and money doing chlorophyll-a tests. Not sure you would get enough information from them to warrant the time money and effort. A secchi disk (purchased or homemade) would be cheaper, quicker, and simpler. Secchi disk will give you a relatively good idea of planktonic algae. If your pond does not contain lots of suspended detritus most of the time all of the variance in secchi readings will be mostly due to planktonic algae. But if you really like monkeying with chemistry then do the chlorophyll a's.

If you do not plan on fertilizing, I would do a few ramdom alkalinity tests at work before you retire. You will find that after the first year or so the total hardness and alkalinity will not change much esp if your pond is in buffered soils. The pH will fluxuate a fair amount when algae blooms are occurring esp in softer waters. I don't get very concerned about pH because fish can tolerate quite a wide range of pH that occurs in most all ponds without having problems. The pH in the anoxic layer will always be lower than in the warm surface layer and pH will continue to decrease in anoxic layer as summer progresses. Fish won't be there so I again don't get too worried about pH in the hypolimnion.

As I said earlier if you don't fertilize the only two perameters I get serious about are DO and temp.

Ortho-phosphate (soluable reactive phosphorus) is a fairly simple test & would maybe interesting for you to test and correlate with secchi disk and chlorophyll-a readings. Again I would not do it unless you enjoy chemical tests or are fertilizing the pond.

Total phosphate is a more difficult test. You have to digest all organics and bind all phosphate before mesuring T.phosphate. Difficult & time consuming test and not really very impt for a small fish pond situation. I would not test ammonia, nitrite or nitrate unless you are fertilizing. Run N03 test monthly at work for the first year and it will not vary a whole lot from that baseline after your first year. Any Questions?

I plan to routinely test for DO, pH, and monitor the temperature at different depths, the nutrient testing is something I will only get into if I have plankton blooming issues. My main concern is the ability to raise a decent population of Large Mouth Bass. I will be adding aeration in the spring, the trench for the power is scheduled to be dug as soon as the rains stop, and I hope to give the fish more 'breathing room' as my pond is over 20 feet deep but only .18 surface acres. I have considered the effect of the mason jar sampler on DO levels and will start out by sampling water from beneath the thermocline and draw samples both by the mason jar method and by using a van duren type sampler which I can borrow for a few days. If there is no appreciable gain the mason jar will do fine but if there is a gain, I have access to argon gas which I use to fill my dry suit when diving in cold water, the argon could be pumped into the mason jar before corking it up and it would eliminate any O2 interaction with the filling of the jar when the cork is pulled. The argon method may be a bit excessive but I do have access to it. Any thoughts?