Wow, you sound very similar to me, inherited pond, same size even, though my pond is above-ground. I just posted a few days ago with similar green water problems but I have had clear water in the past and I do have koi.

I guess I'm questioning your need to deepen the pond to get clear water. I would think if you don't have koi and you have the shade from trees, you might just need a better filtration system? I don't know about bottom drains and skimmers, I guess if you do get a lot of leaves those might help.

I'm debating whether to turn my pond into a flower bed or revamp it, good luck! Sorry I don't really have any more technical advice. What I've learned is that it takes a lot of trial and error to do what nature seems to do pretty well when nature builds a pond!

It may be cheaper to buy a pond kit that has everything with it and has all the parts. Most parts are already precut just glue together.Since you are going to make it bigger anyway. Thats what I ended up doing.

Thanks Cindy! I'll check that site out..I can use all the help I can get. I roamed another site (that shall remain nameless..or I will have my entire, completed followup deleted AGAIN..and be banished to hades, apparently). At nameless, there was high emphasis on DIY components, seemly minimal space constraints, and from the photos I looked at...less emphasis on natural setting than creating a pristine environment for koi. More power to 'em, but I'm striving to build a pond for a natural look and decent amt of plants, minor goldfishes using mostly OTS components with tweakings and DIY parts as necessary based on the guidance from the posts discussions I've observed here.

Today I'll be working up relative component distances, piping runs, lift heights..and hopefully a schematic for review. I'm afraid my post yesterday was too nonspecific for the technical guru's in the group to chime in....

Mew5280, thanks for the commiserating followup, good luck yourself!

Lefty7,thanks for the input. I'd planned on a pond kit until the stark reality of needing a BD was forced upon me by reading discussions in this forum yesterday. Plus I'm enamored with using an external pump to drive the water from the skimmer/BD to the biofalls. Didn't see kits that came close to fitting that bill.

jeff

Working on my plan Stan...and I've got some questions for consideration....

1) I have projected 36 feet of mostly 2-in pipe and 5 feet of vertical lift from the max pond depth (3') to the top of the falls. Looking at pipe friction (including fittings/valves)...I figure 8 feet of lift max. I'd like to get a Performance Pro Cascade 1/8hp-22 external pump...with a compact Savio skimmerfilter and Tetra 3-in BD. Based on the performance chart..I'd be able to get 1,500 gph for my estimated 1000 gal pond. Does this sound reasonable? Will I get enough flow through both skimmer and BD?

2) Will the compact skimmer work for my situation? My rationale: save money because it will work fine for my size pond with a BD.

3) the reason I chose the Cascade pump...is I've heard good things about their reliability...and the watts usage looked good for the gph...and anecdotal evidence to the contrary for folks here? Planning on getting a leaf basket for the input side because I skipped the SC. (I skipped SC because I don't have room for more that a 55-gal barrel...which at my gph and pond size is probably useless.)

2) What do I need to do to set up the Savio compact skimmer for external pumping? I don't see a external pump kit for this smaller skimmer? In particular, how far above the bottom of the pump chamber do I need to terminate the pipe? I assume I will need bulkhead fittings for the exit hole..?

3) Other than the external drain for the Savio waterfall filter...I haven't included any knife valves. If I have ball valves on the pipes to the BD and skimmer, and a ball valve between the pump discharge and falls...why do I need additional knife valves (as alot of folks have advised)?

4) Planning on using PVC DWV pipe...any problems there with the components that I need to hook up that anybody is aware of?

Thanks if advance for guidance/thoughts/advice!

jeff

Plants, plants and more plants especially submerged ones like Anacharis will greatly help in clearing up algae blooms and keeping them from returning.

I think your plan is definitely overkill for what you want but there are many who think you can't have clear water and healthy goldfish without all that fuss. When I read that someone is thinking of filling in their pond, it makes me feel really bad, as ponding is so much fun. Should be anyway. It should not be so frustrating.

My pond is ten years old and I've had one algae bloom when I ripped out too much Anacharis one fall trying to catch extra fish to give away. My pond is 900 gallons, fully rocked (oh, the horror) no bottom drain or skimmer and it is surrounded by deciduous trees and vines that drop flower petals too and overhung by the neighbor's mature fir trees that drop constantly. My filter is a DIY too.

Welcome to the joys of building a pond. I have the Savio compact skimmer (because of it's size). I used a 2" bulkhead fitting in the bottom of the skimmer in that space between the filters and the back of the skimmer. I use a small threaded filter in this bulkhead fitting in the skimmer--just in case small fish came through the skimmer I don't want them in the pump. From the bulkhead I have a short piece about 3" of ABS, then a 90 to bring the pipe up again before going into the pump house. My skimmer and pipework is only about 18" away from the pump. 2" ball valve then a wye as joins the line from my sc. My valves are Ipex valves (given to me by a friend) so have quick disconnects for the pump. I glued the fitting that comes with the skimmer for a submersible pump into the skimmer. The one problem I have with my new pump is that I can no longer run skimmer only when shutting down the sc for water changes. The skimmer draws down too much and the pump wasn't getting enough water. So that might have to be something you calculate for in sizing your pump. In my case I would have to be drawing water from another source-perhaps a midline point but don't have space for any more prefilters before the pump. I also don't have my bd plumbed into the skimmer--someone else will have to advise you on this and draw down issues.
If you do a search on this site there are instructions for installing the Tetra bd. If you rock the bottom of your pond there really isn't much point in the bd as it just won't work. The knife valve is to shut off the flow to the pump and or sc for maintenance. Ball valves are usually used to control the flow of the water. Leaf trap/priming pot even if external pump is in ground is a good idea. I didn't have one and found out the hard way when filter floss got wrapped around the pump. If I had a leaf basket it would have got caught in there. Also the Savio waterfall filters are expensive. A skippy type filter would give you more filtration at about 1/3rd the cost.