Pond Boss Forums AERATION Systems questions Winterization & Algae

Well we finally made up our mind and we are going to try and skate on the pond this winter. We were a little skittish about even trying it but the kids talked me into it. I have about a 1/2 acre pond 12 feet deep with steep banks with a 1/4 hp dual diffuser setup. When do I shut it off? Should I completely shut it off altogether or run it for a few hours each day and gradually shut it off. Also how do I start it up in the spring and when? One more thing, once the weather started getting cooler the filamentatous algae just exploded. I had it during the summer but one application of cutrine plus took care of it. Should I do it again now or just wait until spring so I don't have all that decaying algae in the pond over the winter? I am in Southeastern Michigan by Flint if that makes a difference.

Your location makes a BIG difference.
1. I shut off my diffuser in NW OH a week-ago. Neighbors shut of theirs as much as 3 weeks ago. In the north during November, nature mixes your pond naturally, at this time, usually, you do not need to help her much if at all.

2. Since you will be ice skating - sleding on the pond snow removal will facilitate oxygen production and you should be in good shape for DO all winter.

3. Algae control with copper will not have a lot of affect in this cold water. Since your pond is small, I would remove (lake-rake/net) as much as possible before freeze-up. The remaining algae if it gets sunlight will produce some oxygen under the ice. So make sure you remove some snow around the edges in shallower water. Since the algae bloomed this fall it is what I call a cold water form (could be one or several cold tolerant species). Some limited growth may occur under the ice. It will rebloom again, based on nutrient supply, in early spring when the ice goes off and water is very clear.

Thanks for the info Bill. I lake raked last weekend and plan on finishing it again this weekend and I will shut off the airators. Now I just hope we get a good cold spell before it snows. nothing worse that 8" of snow on a 1/2" of ice. Worth noting, I kept the airators on as long as possible since they push any floating leaves, mainly oaks, to the edge were I can easily remove them. After the big wind storm last week there are no leaves left. How do you start up in the spring? I was running 24/7 and am not sure if I should gradually bring the airator on line or if I should just start at 24/7. Also do I wait for full ice out or turn them on when the ice is unsafe for skating, hopefully in early march or late february.

speaking of winterization, I got a client's system winterized today. I think it was a sweetwater system with the glass jars covering external filter and the check valve at compressor,(not what I use), anyway, when I opened the lid I found out what the suction from the pump through the checkvalve will do to a field mouse. I wish I had a digital camera to show the sadistic people out there. I could still see his nose and tail. A good reason to put the check valves at the diffuser.
Robert B

This is not a good topic title for discussing check valves at the compressor, but a very good case can be made for putting a check valve at the compressor. Ideally the check valve at the compressor should be in-line so the "mouse thing" does not happen. Also to "cover all the bases" or possibilities a check valve should be at the compresssor and the diffuser and I prefer a different style at each location. However in most cases I do not encourage both in most of my sales instances, but I always point out the psssibility to the customer and let them make the decision. I think it really depends on how the system is set up and how carefully it is monitored.

Since the topic title includes WINTERIZATION, I'll post this question here.

I'm getting ready to install a diffuser system in a small, newly built pond. Given my geographic location, ice is one of my concerns. First I will give the layout of the system.

The pond (a dugout stream bed) is located about 20' from my outbuilding. The plan is to house the compressor inside the building. (The compressor will be OFF from early November till late March) I'm going to run 1/2" PVC pipe(underground)from the compressor to the edge of the pond. At this point, I will attach some weighted 1/2" poly tubing to run to the diffuser. Currently, the water level of the pond is about 6" below grade. I can raise the water level by raising the "dam" at the outlet.

My question concerns the hookup (brass barbed fitting and hose clamp) between the PVC and poly tubing. In my area, ice formation can occur from late December and last till early March. Thickness varies. One year I drilled through 18" on my other pond. Should I make the hookup below ice line, 18" below waterline, or can I make the hookup above waterline. Will ice damage the poly tubing or the brass fitting?

Russ

Russ, why take the chance on poly pipe for a short run of 20ft. Consider using weighted (thick wall always flexible)tubing all the way thus not having to worry about condensation or mother nature freezing the brass or PVC pipe,Install in any manner it will not break, just my 2 cents Ted

Fozzybear, after trying to maintain aeration through last winter and dealing with frozen airlines, I have decided not to aerate at all this winter. We also skate, ice fish and drive on the pond and would not risk an accident with thin ice. I will shut down the compressor at first ice, early October and will re-start when completely off, April or May usually. Remove snow from two-thirds of surface once it is safe to walk on and keep it free of snow. I had no fish kill doing this last winter with ice thickness of 36". I did not change my compressor run times at spring startup, 6pm to 8am and my pond did not stratify this year. For me at least, snow removal is more important than winter aeration.

Ted,

Thank you for your reply. I agree with your thoughts of running one piece of thick wall tubing but my plan is more a result of convenience than anything else.

The pond is 80' in diameter. I have a 50' length of 1/2" weighted poly, which will get the diffuser to the middle of the pond. The 20' of 1/2" PVC gets me from the pond edge to the compressor.

I tried an "experiment" yesterday and took a small section of the poly and attached it to a brass fitting and PVC coupling. I taped off the ends, placed the whole deal in a container of water and put it in the freezer. I'm sure this doesn't fully mirror the winter conditions of ice but I thought it was worth a try. This morning it was a solid block of ice with no damage that I could see. I'm going to leave it in the freezer for now while I work on the rest of the system.

Russ

Russ - How bad are your winters? Are you sure you will need to aerate if you keep a fair amount of snow off the pond on a regular basis?. YOu have good depth, a new pond with little organic accumulations, and little weed growth which will all contribute to very slow oxygen loss during winter. Regular Snow removal should be all you need to do. Intermittent Aeration during winter with a fair amount of ice cover can be very problematic.

Bill,

Winters here have gotten quite variable, compared to what I remember as a kid. At times, we've been without snow cover till January, the same can be said for ice.

As mentioned in my earlier post, I do not plan to aerate from November till March. Given the size of the pond, and my desire to ice fish, snow removal will be with snowblower and/or neighborhood kids with shovels.

Given that this is my first aeration system, I'm just wondering about the effects of ice on the airlines.

Russ

If you are not trying to push heated moisture laden air through your cold or subfreezing air lines then you should have no problems. Those who aerate near me have all kinds of piping set-ups and if you dont use them in winter there seems to be no problem if they freeze solid in ice or remain below water or frost line. I have even left quality garden hose used as an airline exposed to winter for several years with little apparent damage. If you still have specific questions about this, form a question and I will address it.

After rereading your Aug 19 post. I think the rigid PVC could be subjected to possibly more damage from ice or UV rays and become brittle quicker or easier than a black polyethylene type tubing. This stuff comes in potable and nonpotable water versions; nonpotable being cheapest.

Do you have a reason why you chose PVC over the black poly pipe which is designed for underground installation? A simple hose barb (plastic or nylon) with clamps could then be used as a coupling between the two air lines. Blk poly pipe is very durable UV resistant and readily withstands freezing.

Snow removal for a pond such as yours would only need about 20% to 30% of the snow removed at least for the first 4 - 5 winters or until you have or develop excessive organics buildup on the bottom going into winter. If you aerate in summer organic build-up should always be minimal.

At a minimum, I recommend you remove snow in 3 strips (1. down the middle, 2. mid way on right side and 3. and mid way on left side). Strips shold be about 4 to 6 feet wide and parallel to the mid-day angle of the sun.

If your water is fairly clear after freeze up (most ponds are) then a 2' to 3' strip around the perimeter over 3 - 4 ft of water also allows light to hit the bottom along the margins and the littoral attached algae growth will make ample oxygen in the shallows.

Bill,

The reason for using PVC was price. A couple of sections of 1/2" (sunlight protected,direct burial) plus some couplings and barbed fittings brought the total to about $10.

Russ