I have read that a pond has to have the water moved 1/2-2 times an hour. It sounds ok for a small or medium sized pond, but for a large one, it would take lots of power to achieve that. For aquarium we usually move water 5-10 times an hour. Does that mean the larger the water, the less movement is required? Is it practical, for instance for a 20,000 G pond, use three solar pumps to achieve 1000 GPH routingly and only use 4000 GPH pump for weekly cleaning and draining?

If it can be done like that, will that cause the bottom drain clogged if the water is moving that slow? In that case, bottom drains maybe should be closed and only open for weekly cleaning.

---Goldfishpal

your water needs to circulate or you'll have dead spots. I Believe your water should circulate at once an hour. I'm not sure though how they do the big 20,000 gallon ponds, but I'd think it'd be the same. I have a 4,000 gallon pond and my pump circulates it at 6,000 gph.

Another thing you have to figure, you have to understand how fast of water flow your filter can handle. If the water is going too fast many filters will not work properly. With a faster flow the water goes through too quickly for the bacteria to grow. I have a sand/pea gravel filter so I can have a large turn over. You need the good bacteria in your filter in order to clean out the ammonia and nitrites from the pond.

Your bottom drain should be going all the time (IMHO), especailly with a pond of that size. If it's not the water will become stagnant and you could get some nasty stuff in the bottom. If you only turned it on once a week I'd think your worries about clogging would be seen.

I'm not sure where you are getting the solar pumps but from what I understand that could be quite spending? Of course you wont have any electrical cost. I suppose it's just what you prefer. My pump is 1hp and uses about the same amount of electricity as a 100 watt light bulb. Most ponds have a 1/4 hp motor (from what I understand), these give the proper flow for the filter that the pond owner has selected.


I am pretty sure though that a 1,000 gph turnover isn't even close to being enough. With 20,000 gallons your not even going to come close to enough oxygen for the fish, unless you are planning on buying an oxygenator? But I would think you are going to need at least three seperate pumps and filter's for this size pond, just my thoughts. Otherwise you are going to have many problems with your fish.


Here is a link on fliteration theory, of course this is the place I bought my sand filter from so they are promoting it. I'm not suggesting this is the way to go I think it may help you to understand a little about filtration.
http://www.bestpondfilters.com/theory.htm


Here is a thread on a large pond being built. I believe it has been in process for two years now. It is huge, and will be beautiful when finished. I am not sure how many gallons, but I don't think it was 20,000 gallons, less I am sure. Thus far from what I've read they are going to use two large nexus filters and 1 ultima II filter. This will be quite an expense, but well worth it to keep the fish healthy. Please chech the thread out. You also may want to pose the same question you gave here there as well.
http://www.koivetforums.com/forums/showthr...65&page=1&pp=15

Scott

Thanks, Scott. It is so cool that your 1HP pump is only 100 watts. I thought it would be 700W, which would become a big concern. I guess I was wrong.

I saw the picture of your pond. I really love it.

There is one question coming up when I read the sand filter page. They realized the speed they push the water does not allow enough time for biofiltration, and they explained that it would be compensated by water passing for multiple times. So it sounds like for the effect of biofiltration, with lower GPH to increase the contacting time, it would have achieved the same effect. So besides biofiltration, is there any additional concerns they did not speak out about moving the water much faster?

Yeah, Tom's pond is going to be close to 20,000 gallons including filter tanks. He is doing it so professionally and is showing us a complete picture of the steps involved. It is funny that he was joking about not letting his wife know the electric bill.

Do you know how large mud farms filtrate? I guess they will count more on algae and surface bacteria. Does bacteria also grow on liner or concrete?

---Goldfishpal

Honestly I am just learning about all of this myself. On the good bacteria I would think it may grow anywhere in the pond? Not sure, but in the biofilter you'll have millions of them and the more surface area your filter media has the more of the good bacteria your going to have. The more the better.

I think Kev Koi or Jetman will probably be able to answer most of these questions for you though.

On my pump, if I turn it up it will use more electricity than what I stated but not much more (just so you understand that).

Scott

Wow, what an amazing documentary!! I am only 1/4 through with reading, but its so fascinating! That Tom guy has an enormous amount of patience, and I can't wait to find out how his pond turns out. I could just go to page 28 and see, but why spoil the surprise!

Yeah, mud pond have much larger mud surface, maybe that is how mud pond works with good bacteria stick to the mud surface.

Larger surface area is definately better for bacteria to grow. But when it comes to the final effect of ammonia and nitrite removal, that surface area has to multiply to the contacting time the bacteria has to work on. This is why I think if the sand filter would need, for instance, three rounds to finish the biofiltration job, then with one third of GPH would have achieve the same effect. For mud pond without much water movement, if we only think about biofiltration, then I would imagine the water layer close to the mud would be cleaned and water layer far from mud would be dirty. So the speed limit in that case would be how fast water layer exchanges. With 1000 GPH water movement using TRP to stir the water that did not pass the pump, I would imagine that should give sufficient water exchange there.

I am just speak out my way of thinking and have no real experiences about what is really happening. But that is the way to design, right?

I saw your complaint about the sand filter got clogged quite frequently. Is there anyway you can watch the sand when they are working? I think the sand need to be blow up and floating in order to have a high water passing rate. I think this is why they suggested only half filling. So maybe you need to turn up your pump to overcome the clog issue.

I also saw you have sucessfully removed the algae. But I think algae is beneficial in term of nitrate removal. So if the algae is only at the surface and is not making the water invisible, then I would rather have some algae stick to the side. I saw some way to control that effect by control the exsposure to light with some blue dye in water. btw, Have you checked the nitrate level of your pond?

Your new pond surface have not established the ecosystem yet. Once that is established, you would not count on only your pump and filters to clean the water. So hang on there and job will become easier and easier.

Thanks for the discussion.

---Goldfishpal