Right, I'm about to move house (Monday in fact!) so it's time for a new pond! It's going to be a streamflow design and I'm trying to maximise the efficiency of this while reducing the maintenance so I'm having the uplifts automated at the deep end dumping onto a bog garden by the pond and the filter will be a surface intake straight over a DIY double sieve then pumped onto a shower. The return water from the shower will return via 4, 3" pipes to the shallow end of the pond to set up the circulating water current. Anyway enough talk, here are the plans;
Plan view,
Side view,
End view,
Side views of the filters,
It's concrete and block construction in 4" blocks backfilled with concrete rather than on their sides, then insulated and glassed. The whole thing will run on one pipe pump rated at 7,500gph at zero head and around 5,000gph at 2m head (the static head from the sieve water level to the shower spray bar should be 1.7m).
The pond will be around 5,000 gallons and about 5m by 3m and 2m deep at the shallow end down to 2.5m at the deep end.
Let me know what you think, any ideas, observations or comments will all be appreciated please.
I'm currently considering something similar myself. There are a couple of issues relating to showers that I wondered if you have definite solutions to ;
1.Given that the returns fom the showers are via 3" pipes to the bottom of the pond will there be enough energy to generate a decent flow to push debris towards the deep end?
2. How do you propose to insulate the showers so that you don't get super cooling during the winter months but have sufficient ventilation for "gassing off"?
3. Have you found a particular pump model to deliver 7.5K gal per hour to the showers?
I'm currently considering something similar myself. There are a couple of issues relating to showers that I wondered if you have definite solutions to ;
1.Given that the returns fom the showers are via 3" pipes to the bottom of the pond will there be enough energy to generate a decent flow to push debris towards the deep end?
2. How do you propose to insulate the showers so that you don't get super cooling during the winter months but have sufficient ventilation for "gassing off"?
3. Have you found a particular pump model to deliver 7.5K gal per hour to the showers?
Regards
Jon
Hi John,
1. Honestly - I don't know for sure! Stuart has said to me that his pond moved the debris down even with only part of his pumps running and when I last chatted to him he didn't think that'd be a problem. Mike S was thinking the gravity flow wouldn't be strong enough and I might need pumps to supplement it! Personally I am pretty positive it will work as I'll have 5,000gph going through the 4 pipes, that's 1,250gph through each 3" pipe and that seems like a pretty good flow rate to me! My back up plan was to either add some air bars halfway up the deep end (though this caused some fine debris to go into suspension and not settle out when Stuart tried it) or to add 3" to 2" reducers in the pipes in the pond to create a localised restriction and increase the velocity at that point without building up too much of an extra head. I went with 3" as that diameter times 4 will allow the amount of flow via gravity, 2" would create too much back pressure.
2. The showers and sieve will be in it's own insulated filter house - another advantage of using pipes to return the water IMHO. I'm going to have kingspan in/on the walls and a polycarbonate roof.
3. I've found a pipe pump (http://www.isleofelykoi.co.uk/hp-33000-p-175.html" onclick="window.open(this.href);return false;) that moves 7,260gph (not 7,500gph, sorry!). At the near 2m head this pond will run at the pump curve I was shown says it will move about 5,000gph. It uses 295W and will have a single 4" pipe to feed to the shower.
1. My concern was that water would back up and overflow from the returns because of pressure from water at the bottom of the pond reducing the flow through the pipes. I wondered given the sheer volume of water being returned whether it would be effective to have the return at surface level raised for maximum turbulence in the summer and just below water level to avoid additional cooling in winter). I think Stuarts pond is a slightly different ball game because he isn't relying solely on showers and uses pumps to return most of his filter flow.
2. In addition to using Kingspan, etc I was hoping to source insulating blocks for construction. I was also going to visit Darren at A4Koi for some advice on how to build the enclosure. I did think of creating a "supershower" rather than use conventional 4-tier units. This would be a cabin lined with Kingspan and fibreglass and have shelves for the BHM. I was also thinking of installing some sort of heating device to negate cooling.
3. Thanks for the pump link. I knew there was one out there but couldn't think what it was called or who stocked.
I haven't as yet got any drawings. I've been chewing over building a streamflow the pond for about a year - I saw Stuart's pond build thread, then Mike S very kindly took there on a visit (it was even more impressive than the thread suggested). The reason for the delay in starting the build was that I was going to build the whole thing in a cow shed, but I kept finding more logistical problems - digging into hard rock in a restricted space, accesibility for ready mix, etc, so I've now settled on an outside side. However I still wanted a shower based system. So basically I'm looking at a rectangular pond 8K gals with showers and some sort of water polishing device - bead filter or static K1to improve clarity. I was going to pop up to A4Koi to seek further advice once I'd got something down on paper.
Jon W wrote:1. My concern was that water would back up and overflow from the returns because of pressure from water at the bottom of the pond reducing the flow through the pipes. I wondered given the sheer volume of water being returned whether it would be effective to have the return at surface level raised for maximum turbulence in the summer and just below water level to avoid additional cooling in winter). I think Stuarts pond is a slightly different ball game because he isn't relying solely on showers and uses pumps to return most of his filter flow.
This can't happen with the 4, 3" pipes I'll be using. There's no extra pressure affecting the returns really as they are flowing via gravity, once water is added to the top of the pipes in the shower the weight forces the water out the pipe at the bottom in the pond, just because it's below water it won't change how this works. If you're going to use pumps to create the flow patterns then I don't suppose it really matter how or where you return the water as long as it doesn't conflict with the flow patterns you're trying to produce. In other words don't have surface return pointing down towards the deep end as the surface water will go from the deep end to the shallow end. Does that make sense?
As I said earlier, if anything I think I might need to throttle the size down to increase the velocity. Basically I worked out the gravity flow by using the often quoted amounts for gravity for 4" pipe and then applied that to other sizes using a pipe equation. These pipes should lead to the water in the shower tray at the bottom being practically the same height as the pond. Either way I want the bottom tray to have some water in the base as I've heard that pipe returns from showers can gurgle and spit bubbles out otherwise. So if it has a few extra inches water it won't make any difference except for submerging a bit more of the media.
I just don't see why the returns from the shower can't provide that water current configured this way rather than use extra pumps (at extra cost of both purchase and running costs) to provide it.
Looks great Ed and hope all goes well with the move
I think the head from the showers will be OK and the water will get back to the pond OK as i know Darren's (A4 Koi) runs his main ponds this way although he is pumping a fair amount but he does have four 4" returns back to the pond.
Cheers Gaz, hopefully the move should be pretty painless!
I'm more worried if the flow coming out of the 3" pipes will be strong enough to get the current flowing along the slope down towards the sumps. I reckon it will but every streamflow pond I've seen uses pumped returns rather than gravity ones to generate the flow.
If you are not sure how about raising the shower as high as you can so it has a better head for the drop
I don't think that would make any difference Gazza as the water will just find it's own level within the pipes rather than in the bottom tray of the shower. As far as I understand it the only way to gain any benefit from that would be to fit smaller diameter pipes which would increase the frictional resistance increasing the head and meaning the water would have to increase in velocity ( produced from a higher head in the shower) to compensate.
I am 90% sure it will work as it is; I'm just being very cautious as Mike S wasn't too sure and he knows his stuff! He's made me a bit paranoid about it!
If the shower was higher then the water would have more of a drop which should increase the flow due to the fall but as you say i don't think it will be much of a problem to be honest.
If its the current and water mixing your worried about just think once you get the system running and the fish in they will be loving it so much they will be whizzing around and making the water move all over the show
Cheers Gazza - I'm hoping that'll be the effect anyway! Re-read Stuart T's, "Pond Breaks Man" thread on Maurice's site yesterday and he got the sweeping effect when only the bakki shower was running on the top of the pond at the shallow end and Al had to reduce his flow along the bottom of his as it was too much so I reckon a large, more gentle flow should work well. I can always use some air at the deep end if I need to.
Now I just need to work out how exactly to build the DIY sieve! Got a few ideas I'm mulling over!
I am running a remote shower ; the single 4” return is 6m away from the outlet into the pond that is at 3' depth below the water line.
It copes easily with 3 Eco 16000s going over it, given the head etc and restrictions due to HX etc these are probably delivering about 30000L over the shower so 6500gph, maybe a bit more.
The bottom of the shower box is 12” above the water level.
Problem that I had is with air being drawn through the return pipe even at this flow.
So it was a question of either 1) throwing even more water over the shower or 2) putting a valve in the return to restrict the water going through, this give me a head at the shower box end 3) adding extra returns so that the flow through each was reduced and they didn’t gulp water from the shower box.
I went for option 2) and it has done the job, slide valve in there that is approx 30% closed gives me a constant 3” in the shower box.
Looking at your suggestions - sure you can do the maths but in terms of simple pipe surface areas - 2 x 3” returns will give you slightly more gravity flow than my single 4”, 4 x 2” would give you around the same. Ok this is simplistic as it starts to get complicated when you add frictional losses that will be greater in the multiple small bore option..
Think if you went for 3 or 4 x 3” returns all with valves you would be able to balance the flow nicely.
Cheers Dave. I've read about people's experience of gurgling with remote showers and my plan to stop this was just to lower the shower. My plan at the moment is to have 4 proper stainless steel Bakki shower trays (arranged in two stacks of two) above a much bigger fibreglass tray. This fibreglass tray will sit with the bottom 4-6" below water level so there will be water in the bottom of that tray all the time.
I am hoping this will do three things -
1. Stop any air going down the return pipes (and therefore any gurgling).
2. Allow any foam generated by the shower to collect in that tray (and then be removed somehow which I haven't figured out yet) to work a bit like a clarity unit.
3. Reduce the static head I'm pumping water up to giving me a greater circulation for the same wattage.
I've worked out 4, 3" pipes should return the 5,000gph without any head but it's amazing to hear just how much water can go through 1, 4" pipe!!! What's the flow like from your pipe when it returns back into the pond? Does it noticeably help with the circulation or have you got other pumps/airstones circulating the water in the pond?
At the outset I didn't intend to throw quite so much over it but it kind of evolved.
It does come out at quite a pace.. will throw any particles 8' or so before they start to fall.
Problem is think Ive established the return can cope with a second shower so just gotta find the cash..
If I get some time tomorrow afternoon I will open up the slide valve on the return and have a measure of the head loss with 1,2and 3 pumps working, nothing scientific but may give a few pointers.
