You have a lot of questions but you gave much more info than most newbies it makes up for it. LOL! I can't answer all your questions but there will be others along to correct that. No one pond is exactly like another and no ponder is just like another. I can't quite visualize your pond but maybe it will come clearer later on. You don't say why the pumps fail. If it is the same reason each time then I would think you should go to another type altogether. Or provide what it is lacking. If debris is damaging the pump then you need a prefilter which prevents damage to the impeller. Most pumps have a small and totally inadequate sponge in front of the impeller. Most of us toss it and install some sort of prefilter in it's place. Looking at your pump, I don't see even that, just a cap with lots of slots for water flow. Options could be change pump type, or remove filter cap and attach prefilter with sponge or other filter material. Algae is endemic when the pond gets lots of sun. You could use lots of chemicals but that is rarely satisfactory. A UV filter could work just fine by using a diverter or adding a small pump and filter. With your waterfall pump I suspect a separate pump would be easiest. More later, Sandy

Hi all - wow thank you for the input! For some reason a few of these comments never made it to me via email, so sorry for the delay in response. CHAS: I think I'm going to just go with a shorter stream, which will cut down on the height a great deal. I will wrap it around the pond (instead of going straight up the sloped ground) - which will make the head height less and also keep the flow calmer for froggies. I also decided that I will focus the main pond on fish; and I'm going to put a little, shallower pond tucked along the creek which will be just for frogs - with a pump maybe, but no filter or anything (my current frog pond has just a pump/waterfall, no filter, and the frogs are very happy and healthy there). Hopefully the frogs will natuarlly choose the little pond instead of the bigger pond, and even if they lay eggs in the lower pond, I can just move them up to the froggie pond. I at least will feel like I've done my part to provide a safe haven for them :) RSINGLEY: I had read a similar recommendation elsewhere of putting mesh and other media around the pump - I like the idea, though I do wonder what the negative effect of not filtering the larger particles will be? (seems silly to get a debris handling pump and then restrict the debris from getting in, but alas, the dilemma of tadpole lovers). FROGMAN4: You'd be right on the calculation but it's not all at a 3.5' depth, and it's an oval pond. If you picture an upside down oval wedding cake: the biggest layer is 16x13 but it's only about a half-foot deep (it's a rock shelf). The second layer is 14x11 and is 1 foot deep. The third layer is 11x8 and is 2 feet deep (so total depth at the bottom will be 3.5). I calculated each "layer" out as separate pond volumes; using the oval pond forumla of L x W x D x 6.7, the top layer is 696 gallons, 2nd layer is 1031, 3rd layer is 1179 = 2906 gallons. The third (bottom) layer will have sloped walls, too, which actually will cut down the gallons, but I'm fine with over-estimating. I have wavered back and forth a hundred times about going with a skimmer filter as opposed to an external mechanical filter. I still haven't hit the "place order" button on my pump/filter order, but I made up my mind last night that I was going to go with a Laguna max flow pump (2000 gal), pressurized filter (3200), and also have a waterfall bio filter at the top. Holding off on the drain for now, but I saw some that I can add later if the need warrants. Chose the external filter instead of skimmer because I didn't want to have to do 2 pumps, and I just felt that not having the pump at the bottom (which it wouldn't be if I put the pump in the skimmer) wasn't the best idea... which was my deciding factor. I hope what I'm choosing will be sufficient... weeks of research got me here, and I'm ready to just install all this already! :) MEGANMCA: Thanks for that link - it's very helpful! I did read that pipe diameter is important - I'm going to go with 1.5" and hope that's sufficient. My sister just installed the same pump/filter combo I'm using with 1.5" and it's a beatuful flow. Her waterfall is a little lower than mine, but I think it will suffice... If not, can add a 2nd pump but hoping I don't have to do that. Thank you all so much for the input - and as always open to any other thoughts/suggestions!

I did pipe boot connections on my retrodrain through the wall of the pond. Didn't make my hole as large as what Horton suggested--only 1/2 the diameter of whatever size pipe. Most recent was 3" and made a 1 1/2" hole in the centre of where I wanted the pipe. The liner stretches but it takes strong fingers. Easy to do and as far as I know no leaks. Curious why aren't you looking at external pumps for your pond? They are more energy efficient, easy to winterize. I have a priming pot on both of mine even though they are below ground but had a problem with quilt batting getting wrapped around the impeller of the older pump before using a priming pot. I have a Sequel 4350GPH pump that is very quiet uses 175W. This year I plumbed this pump to my sc and the old pump (Sequence 750 4200GPH but only pumping about 1/2 of that due to bent shaft) to my skimmer. I probably don't need both pumps as also changed my waterfall out this year so is smaller. The Sequence is noisy and leaks a little on start up around the shaft. Long story short I love the external pumps. Aquaart carries good external pumps and also the bottom drain that is mentioned either here or other forums. I also like the skimmer--it collects alot of surface stuff like dust! In the fall I run my pond on the skimmer only so that I can remove my drains (have a midwater drain now which is also awesome) before the water gets too cold. Like Horton my pumps/sc are hidden under a deck. Two pummps might be an idea for your pond as you need less flow through your biofilter and more flow through your waterfall. One idea I saw here if you only use one pump and need the circulation (in your case at least 5000GPH) was to pump part of the water back into the main pond and the rest through the biofilter/stream. Aquaart has a diagram of how to do this. As for valves depends on if you have a drain on you skippy filter etc. I have a knife valve between pond and sc on the bd but on the midwater drain which also goes into sc I don''t--I use a standpipe. After skimmer and sc 2" ball valves--I know could have used knife valves there but ball valves are more reliable. My check valves are after the pump but before the ball valves to the waterfall filters. This is to keep the water from the waterfall filters coming back down through the pump and into the pond if power goes off which it does here frequently. Because I have priming pots, sc and skimmer I don't need check valve before the pump. Can't remember when you need check valve before the pump--sorry. Ball valves after the check valves to control flow to filters. I know that I could get away with running one pump now due to the changes I made in adding a midwater drain to my sc (had alot of draw down!) and waterfall changes as the valve on my Sequel pump to higher waterfall is turned down more than 1/3rd. It's just time consuming and more pipe to change it out again. I don't know if you are allowed to use ABS in the US. I use it here as fittings are available and it stands up to my climate. Also because it's black any pipework in the pond lie retro bd don't show as much. You have a fun project on your hands! It can get rather overwhelming but there are many knowledgable people on this forum who can help you. Good luck. Patti

I know our pond was discussed in detail on some koi forums, it was bought up by Roddy Conrad (many years ago) he discussed how we manage to successfully maintain clean and healthy pond practices with aggressive water exchanges and a separate biological pond. I read many of the posts with Roddy but unfortunately missed yours. Water changes and flow thru systems have of course been a cornerstone of fish keeping, from fish farms and hatcheries to backyard ponds forever. Many of the Japanese growers seem to have flow thru systems, but most of us don't have a stream/river in our back yards for that so we have to make due with water changes. Up until the last few years most of the discussion in Koi Ponds has been about how frequency relates to keeping fish alive. In the last few years it's changed by a very few people to frequency relating to other things like clear water. algae control, and increasing fish growth. It's new so interesting to me. What surprised me is that you are already basically doing the 24/7 drip thing except once a day instead of 24/7 and hose instead of drip. Your volume is right in the range of 10-70% per week (varies by goals). And you've been doing it for a really long time so that's good data. Not sure how long Andy Moo has been doing 24/7, he's been around a long time too. And of course you're also using your hose as a TPR and basically the same as vacuum. Whether dirt is pushed to suction or suction is moved to dirt the result is the same. And you're doing it often. Pretty much all the people I've dealt with who wanted a bottom system as a option (not required for fish load) wanted it solely as a convenience. They just want a pond for looking at fish after work and don't want to pick up a hose. I do not belong to any of these forums, ( I did try briefly, however they were beyond snobby) as they have very expensive Japanese koi and they have sterile ponds, (meaning no rocks on the edges) also their filtration systems cost many thousands of dollars and they are quite snobby about their koi and ponds. Hell they don't even consider butterfly koi to be koi. Every forum seems to have a single specific type of pond that the 20-40 dominating posters have. Every forum says they accept all kinds of ponds but that sure isn't true. They'll say "all ponds are different, and that's great" and then launch into telling people why their pond is all wrong. But that's forums, protecting their little world. I most read pond forums that sometimes have good info but I don't find much reason to post very often. I've learned a lot about that I might be able to adapt to other ponds and more importantly so I understand these systems. Aquarium forums are even better for learning but I never post in those since I've never even had an aquarium or are interested in one. But those folks sure know there stuff, lots of test data. I think the hard it is to keep fish alive the better the forum because they have to take everything more serious. Fish farming forums are good too. If it don't pay they don't use it. However, the main reason I won't frequent these koi forums is because with all their expensive and super elaborate filter systems -- many of them they still use PP to help clear their ponds. I don't get it, why subject your fish to dangerous chemicals? If you systems are so wonderful why do they need chemicals and uv lights? You can see the amount of trouble I could get myself into frequenting these forums. :) Besides, my koi are mutts. I haven't seen much in those forums about PP use for general maintenance in several years. Occasional use by few for a specific reason. Or maybe they just don't talk about it. There's been better filters developed since Roddy was talking about PP and way easier to use, and pretty cheap, oxidizers have become available since then too. They need those things because they keep a different kind of pond than you do. For example for me to do the kind of water changes in San Jose would have added about $80 per month to my water bill since they use a tried system. While $960 a year isn't a lot I kept the water clear enough for me using other cheaper means. It's just a choice thing. For my next pond I can design a pond specifically to include 24/7 drip so I can reuse the waste water for landscaping. Here in Phoenix we water the landscape all year, and use a lot of water for that. So the water from the 24/7 drip will be basically free. Free and completely automated me likes. I know Dr. Roddy Conrad from another forum that we were both members of. We got along well,( but I did disagree with his PP practices.) He knew our set-up that why he was able to explain to the koi forum members our set up and aggressive water exchanges. "Successful pond husbantry practices " he called it. I don't remember if the other forum members agreed with him. Probably not. The Doctor that lost all the koi in his pond (twice) was that from on overdose of PP? I don't think I've ever posted directly with Roddy but have reads hundreds of his posts. He may have taught me more about ponds than maybe anyone else, especially when I was first learning about koi keeping. I've just been interested in learning different techniques and don't really have an opinion on whether it's good or bad. Just a tool. A hammer is good for driving a nail, not good for opening eggs. The tool itself is neither good or bad to me. I don't find a lot applications for PP but when needed and useful it works fine. But I'm sure happy Roddy took the time to teach me how to use PP, it's effects, and it's downsides through his posts. I'd be happy to buy him dinner any day. Plus his explaining, experimenting and providing lots of early data on Trickle Towers was very important to the hobby imo. And he took a lot of crap from the peanut gallery to boot which taught me a lot about forums which has helped me in developing software. TT popularity may have been short lived in the Koi Pond world but lead to even better filters. So I take what I can from those forums and just try and stay out of the crap...as best I can.