Ive got a pond with a secchi of about .3 ft (planktonic algae). Keep in mind were in michigan and we like our water to have a secchi of about a mile. (I try to tell folks to keep a little algae, but they want swimming pools) Total Phosphorus in the pond is 1.19, nitrates are .6 and nitrites are .01. Im assuming we have a phosphorus issue. Now where do I go from here? The pond is 4 acres X 4ft deep avg and aerated with a 6 plate system (2 3/4hp rotary vane). Am I under aerated or should I look at Alum?
What do you want to do/accomplish ?
we're looking for clear water, no algae, more or less no plants.
What about fish ? I don't think alum used as intended will be an answer to plankton density. It will help knock out some of the suspended solids.
I thought that alum bound up a good amount of phosphorus, which is what I think the problem is. Fish are not really a goal, just innocent bystanders in this one.
It can but it does not bind up the P in the soil. There are possible sewer treatment products that may do that but I have not heard of anyone doing that to a pond bottom and watershed. Have you had the soil tested ? If there has been no fertilization then I assume the P source is the dirt. I also am not sure about the long term reabsobshion of the initially bound P out of the alum/P bond by the more acid water due to treatment.
I would want to know for sure if the P is high from a soil test before I started spending $ on alum and what the long term effect would be.
P - tests in the past have not shown outrageously high amounts, just this summer. I suspect that the lower than normal rainfall last year and the much higher than normal rainfall this year has created a large influx of P from the watershed (lots of fertilized lawns). This pond is also linked to several other ponds in the community, so I believe that it is a cumulative effect.
How can I test the soil? Are those diy garden tests sufficient or should I send it in?
If you know you will have runoff from fertilized lawns and it is likely to keep occurring then it will be very hard to limit the incoming nutrients. I don't think in that case the constant adding of alum to the pond will be efficient or work well. That leaves 2 approaches. One treat with something to kill or limit the plankton (as fish are a small concern) or two look into one of the waste water/landfill products to bond P to the soil over a large area. May be others I am missing.
From the archives - Soil & Water test links
Soil Test Laboratories in Michigan
Soil & Plant Nutrient Lab
Michigan State University
Plant & Soil Sciences Building, Rm. A-81
East Lansing, MI 48824-1325
(517) 355-0218
Although you can send your soil sample directly to the lab, your best bet is to contact your local extension office to obtain a soil collection kit and fee schedule. (The lab will direct you to your local extension office if necessary.) Your soil test results will be sent to your extension office.
Justin,As far as under aerated when you say 6 plate system are you using 6 plates of 4 stones such as ALA4GL or the 6 per plate ALA6GL ? If 4 stone plates are being used (and Im going to make some general assumptions so correct me where needed)you may be under aerated, If you have 20 available CFM and 3.33 cfm per station you may want to add some additional diffusers. I believe the operating range for the 4 plate is somewhere around 2.4 cfm max.which means you could add 2-3 additional plates if you stay with that model.This is also assuming the pumps are 10 psi models and not 15 psi models which provide less cfm's.Your total lift which is probably in the 1.3- 1.6 turns per 24 hours may be fine but all of the gallons probably arent being effected since you have shallow water.Im using diffusers in 6 ft minimum depth of water .Also if these are square stones turn them on "edge" on the plate to expose more of the total surface area vs the way I usually see them mounted flat with only 75% (3 sides) exposed.Is Hydrothol 191 out of the question for the goals listed ??I also thought Michigan had gone to a zero "P" in the lawn care industry.
Commercially I think the zero P is common, but individual homeowners still load up on the P. They are 4 stone plates. Have you had good results with Hydrothol 191? I like it but usually can't use it due to irrigation restrictions so I don't have much experience with it for Planktonic.
Do you have any links for the math behind aeration installs?
Im sure your correct on the commercial P and tough to police homeowners. Perhaps costs of fertilizer for next year will curb some of it as my cost has doubled since last November.I realize many Lowes type stores will always use it as a lost leader type product but I see they too are offering P free.When I have swimming pool goals with an occasional fish thrown in I do use 191 and like it. Shallow water ponds are still my most difficult but I find turns that are one plus usually disturb planktonic algae formation,this is why you may be able to add plates if you have area or pockets that are not being effected by aeration. Knowing that it takes very litle available P to have planktonic algae I think anything you do may only be a temp solution.What type of math are you referring to on the installs
So hydrothol 191 keeps planktonic down well, even in large lakes? Cost is a big issue on this one, but I'll do it if it works. I like it in small ponds and trout/koi ponds. I'm gathering from my research that locking up the phosphorus is about out of the question. Math-wise i just like seeing any differing views to hopefully learn more. Just want any sites or info for calculating systems
I would test 191 on a small inhouse basis to see if it meets your need, as yes its costly. If any irrigation needed I would not trust the restriction guide,if you irrigate do not use would be my policy.I have the same policy on Sonar as it is difficult to get it to test to safe levels,you then also have to consider landscape plants for which tests probably have not been done.Ill see if Sue at Vertex has a file she can post on the testing and lift data for their systems for an example. I have the test results on our site under "A word about diffusers" Ill see if she will do a sample of a 4 acre lake with a 6 ft average depth and a desired turn of twice per day (for information purposes) not trying to advertise . If the moderators would rather this be PM'd to you we can do that too.
Depending on the situation I have used the following as an emergency method to reduce planktonic algae that was to dense.
Take a 5 gal bucket and put a hand full (estimate 4-6 ozs) of CUSO4 in the bucket add 3 gal of water and stir until dissolved. This produces blue water. Take a hand sprayer (3 gal) and add the blue water 1/8 and clean water 7/8 to fill. Spray from boat lightly over about 15% of the surface area in parts. For example small areas of about 3% in 5 different areas leaving untreated areas in-between. It has when used reduced my plankton densities by about 40% on a temporary basis. It does carry a high risk and you have the potential for CU accumulation in the system (bottom muds).
This is my last ditch emergency plankton reduction method. I am not sure what the effect of doing this with aeration ongoing would be.
I've been using CuSO4 to knock it back with short term results. Is there any way to convince someone that planktonic is healthy for a pond? It would be much easier if folks would agree that green, productive water is much better (and easier to maintain)than crystal clear swimming pool water. Sometimes.... I'd like to throw things.
I feel your pain and frustration. No magic suggestions on that one.
But the answer is in your words--MAGIC. We always keep a pail of it in our trucks, just incase someone needs it! You want your duckweed gone today? I'll get out the magic! You have one weed growing after I killed 99% of the weeds in your pond? No problem sir, I've got magic with me today. lol, But I Digress.....
Jmac, the alum may be your cheapest swag at the problem. It will bind the P and should also floc most of the planktonic from the water.
I'm going to throw something out here since it appears to be the root of this problem.
I'm guilty of fertilizing my lawn. Go ahead and shoot me. I like green grass and the healthier it is the less weeds I have to kill. I tried several brands and kinds of fertilizer with a wide range of effects. One , 15/15/20 mix from the grainery caused nearly flourescent green streaks in the water almost imediately after a rain. Other types simply made my grass grow like crazy.
Currently I'm using something that starts with an Sc and ends with ott's. It's their cheaper line and has 2% iron too. It's 29-3-4 and slow release. I have had no problems and almost no weeds in the pond even though I fertilize right up to the edge (a slightly lower rate around the pond). It keeps the grass nice and green and doesn't seem to need to be mowed more then unfertilized lawns.
Maybe you're neighbors need some encouragement to simply change brands or suppliers. I'm curious if most of your neighbors are receiving their treatments by spray from the back of a truck. I haven't been too impressed by the spray truck guys I've encountered or their products and "professional" granular application is often a competitively priced alternative.
Ryan, that is some great looking grass. Are those cows yours too?
Thanks rmedgar. The cows belong to my neighbor, they're a constant source of entertainment. My brother lives in the homestead, he has longhorns.
Fertilize the yard, not the pasture. What a concept ...
Theo, I heard you cock your hammer clear over hear in Plain City right after I clicked the the post button.
Hi guys: Theo suggested that I bring this to forum, and since fertilization has some what of an effect on ph an alkalinity here goes: My new pond (5-08) has a very hard, clay bottom and the run off comes from rocky, redish soil. We have a normal amount of alge, etc with some water plants beginning to appear. Haven't stocked it yet, and won't till water temp get about 70-74 this fall. My Ph at 3:00 pm yesterday was 9.3 and my alkalinity was 60 ppm. I think I'd like by alk. to be about 100-125 ppm and my Ph between 7-8.5. I know the Ph is a moving target depending on time of day and other factors. Should I be worried about 9.3Ph at mid day, and if I use pelletizied lime to up my alk. would it totally spike my Ph and fry anything living in the water. I'm not adversed to using small amounts of muratic acid to help the Ph process, but I'd really like some "expert" input. Thanks guys. Jimmydee
Interesting question Jimmy (which of course means that I have absolutely no answer), bump to the top for ya.
Experts?
jimmydee let me make two suggestions. Have your soil tested in your watershed and pond bottom , if different. This will provide you advice based on your dirt and a baseline to work from.
Mo. ----
Soil Testing Lab
23 Mumford Hall
University of Missouri
Columbia, MO 65211
(314) 882-0623
Contact your local extension agent or the lab listed above for soil collection materials. You can mail samples directly to the lab or to your local extension agent, but all results and recommendations will be sent to the agent, who makes recommendations and forwards the bundle to you.
Go to this link and read SARC 464. Don't worry about the complexity but it will give you a good info base. The second link below is to a very good pond water quality article by Aqua-NIc
http://srac.tamu.edu/index.cfm?catid=25SRAC 464 Interactions of pH, Carbon Dioxide, Alkalinity
and Hardness in Fish Ponds
http://aquanic.org/publicat/state/il-in/as-503.htmWhat do you want to put in the pond ? Most pond fish will do fine in 60 alkalinity water. Can you check the pH early in the am ?
Thanks guys: Checked the Ph at 8:30 this am and it was in the 7.9-8.2 range, (compared to over 9 at 3:00pm two days ago), so it is truly a moving target. My alkalinity was right at 60ppm, exactly where it was during the test two days ago. I think I'll keep monitoring it daily at different times of the day, and if this Ph thing seems to fluctuate in the 7.5-9.0 range, I'm not going to "fix" it. To answer the stocking question: I'll be putting in about 200 BG, about 150 RE, and about 10 lb of FH (300 per lb). Next June I'll add 50 LMB as 1-3" fingerlings after the BG and RE have spawned. Sound OK???? Guys, have a great week end. Jimmydee
Those fish will do fine in 60 alkalinity and 8 pH.