So here I am counting the days until the winter is over and I can move on with the big pond expansion. What better to do than spend all my time planning, re-planning and planning some more?

As I plan on keeping a couple koi, it seems the consensus on this forum is that a bottom drain is a good idea. I could really use some feedback on my bottom drain plan.

Okay, here's the plan. I will have some sort of bottom drain (and, heck, if I'm brave I might even put in an aerated one). The plumbing from the drain will run to 2 or 3 35 gallon rubbermaid type tubs connected together via bulkhead fittings and pvc. The tubs will be buried in the ground so that when filled with water, the water surface in the tubs will be the same as the pond surface level (am I making any sense??). The first will act as a sort of semi-settlement chamber, the second will provide some basic mechanical filtration and contain the 2900 gph submersible pump (or maybe the pump in a 3rd tub). From there, the water will go to a bio-falls filter thingie and back into the pond.

I'm not going to pump the water from the drain to a skimmer application because I already have an Oase Aqua Skim running on another pump and an Oase Swimskim running around the pond (just because it was neat and I'm easily amused. Surprisingly works really well!)

I was planning on sinking a few tubs next to the pond for marginal plants anyway. So, I figured I can also use them to perform some mechanical filtration while I'm at it.

So, finally, here's the question. What you all think? Stupid plan? Good idea but with some tweaks? Should I think about putting a bottom drain in the first rubbermaid tub to drain out the fishie poop? Any input is very much appreciated! I could use some ideas about filtration media, the best way to clean the tubs without making a huge mess (i.e. I don't want to be plunging my hands up to my wrists in fish poo during the weekly clean outs if I can help it!)

I read somewhere that most DIY ponders finally "get it right" on their 3rd pond. I'm hoping that I can get it right with my second pond with all the help of the people here and the 6 months of upcoming winter in which I will have nothing to do but think and plan!

Thanks in advance for all the help!

Jenny

PS Big thanks to Cliff and JoAnn whom I borrowed very heavily from for my filtration plan. Oh who the heck am I kidding? I have Cliff's hand drawn plans saved to my desk top and am copying them pretty much verbatim minus the biological filtration pond!

If I install a bottom drain, what about freezing? How am I gonna keep the pipe running from the drain up to my ground level mechanical filtration tub from cracking in the winter? Can I run standard PVC below the frost line and use flexible PVC closer to ground level where freezing and cracking is likely to happen (just for cost concerns)? Is it even wise to leave water in flexible PVC to freeze up in the winter time?

Again thank goodness I have time to think this through. Had this been May, I would have had a bottom drain installed and would right about this time next year be worrying about the 4" PVC that I had installed cracking open with frozen pond water!

PS Again, thank you to all the forum ponders for your patience with all my questions. I read everything I could find on here about bottom drains and learned a lot....and just enough to cause me to have more questions. Because of the really, really cold winters I live in, I have a bit more to consider with plumbing stuff.

Now if your 2900 gph pump is able to pump 2500 gph based on your head pressure then to get a settling tank to work properly it would have to be about 833 gallons and built correctly to get it to work correctly.
Mike

Joann

Mike...the surface area will be approximately 15' x 9'. The pond will be connected to another pre-existing - and too small - pond that is about 6' x 8'

Joann...my pond setup will be similar to yours. I've been inspired by your expansion. The expansion will be about 15' x 9' irregular kidney shape, 4 to 4 1/2' at its deepest for overwintering fish with a very shallow "beach" end. The bottom drain will be going into the 4' part of the pond. Not sure what I will do about the original 6' x 8' pond as far as bottom drains go. Ehhh, watching ebay for pond vacuums. Maybe can get up the fish poo in that portion with weekly quick vacuum.

Not sure how many fish I will get. Thinking of probably 3 to 4 koi and a few goldies. Maybe a bottom drain is overkill with the fish load I'm considering. But, I'm planning ahead because knowing myself very well, I know that I don't do anything halfway; just ask the half dozen people I've given cat condos, toys, litter boxes, heated beds, etc to because I had so much stuff for just my 2 cats! I just got a feeling I'm gonna love my water "puppies" as much as I do my feline friends and want to make sure I give them the very best I can!

I just saw your reply on another thread about bottom drains from 2007. Wonder why I couldn't find it before...but it answered a LOT, LOT of my questions!

As you said to the OP...thank goodness I have all winter to think about it!

Keep in mind we built our pond in 1997, that was the dark ages as far as the internet was concerned. We took books out of the library and then went shopping for a liner (nowhere was a bottom drain ever mentioned) Fortunately
for us we shopped in a large pet store that sold pond supplies and liners. The owner had a large pond in his backyard and explained to us the necessity of the bottom drain and the dome top on the bottom drain.
The pond floor is all slightly tilted toward the bottom drain to enable all the muck that settles on the bottom
to naturally gravitate towards the drain. The water swirles around the drain with the dome top and flows through the drain into the tubs.
The first and second tubs have the filter material. We cut sides of milk crates and wrap them in various materials like cotton batting and force them standing straigt up into the tubs. Most of the waste is trapped into the first tub. The last tubs hold our pumps, we have about 5 or 6 pumps ranging from 1200 gph to 500 gph. We usually have
2 going all the time one for the main pond and one for the biological pond, which we added the next year... (more about that another time) We like to have several small waterfalls
all over the place, that's why we have several pumps. Another reason for the different sizes of pumps is we have more control over the flow. When the filters are in need of a cleaning the flow of water slows down and we have to slow down the pumps.

If you want koi, forget about goldfish. The goldfish multiply like crazy and soon you'll be trying to catch them to give them away. We only have two goldfish (our original goldfish that are 12 years old) We also have 3 orfs they are the population control in our pond...

One more recommendation, think about using a 4" drain.
We have a 3" but if we were doing a pond today we would use
a 4" drain.

The shelf, be sure to build a shelf all around, ours is
deep and wide -- we then built up to ground level with rocks.

The only place we don't have a shelf is in the beach area.
We also replaced all our small beach pebbles the next year with bigger round stones. It's easier to keep it clean, we hose it out about every two week, and when the rocks start to get an alge build up, we just turn them over to show a nice clean and shiny side.

Our beach is about 5 foot x 4 foot, maybe a little bigger...

Joann

More beach...

Also thanks for the shelf/pond construction tip. I liked it much better than the technique I used on my first pond. Can you bank or backfill the dirt at ground level behind the liner a bit to keep run off from the yard from going in the pond? Unfortunately, my backyard is very downward sloped. It took me forever to level out a spot for the current pond, but you work with what you got.

One last thing...this is the part that is really flummoxing me. What do you do in winter to keep the bottom drain plumbing that runs to your tubs from freezing? I know all about global warming and stuff - and its true...it's 50 degrees today in the northwoods of Wiscosnin, gun deer season starts tomorrow in the state and I can remember having several inches of snow by this time of the year when I was a girl. But, there usually is a 2 week cold snap in January where the temps will go down to -20 to -25 overnight and barely get out of the single digits during the day. It would be heartbreaking to put all the work into digging and putting in the underground plumbing to have it all crack on me!

Thanks again Joann!

You and your husband's pond experience has been so very, very helpful and appreciated by this new to the hobby, but no less enthusiastic pond addict!

Jenny

PS thanks for the tip on goldies! I imagine schools of goldfish would have been too much for my cats to ignore and I would have ended up rescuing a drowning cat at some point and/or repairing holes in the liner sides from the cats' frantic attempts to claw their way out of there!

We didn't need to backfill the ground around the pond.

As far as the freezing goes, I hope some zone 3 ponders can jump in and help you, (we're in zone7) We cover our filter tubs with bags of leaves to keep the tubs warm. The last few winters we have been keeping one pump running (a 250 gph pump) so the pond is operational all winter.

This is a photo of Momma (the Terminator) and her baby 'spun gold' she's bright like shiny gold.
One thing about gold koi you can spot them for down the block. :) 7-27-09

This is a shot of the dog leg. Notice all the rocks they knocked off the shelves and out of the pots. Koi are hopeless diggers. Cliff goes in the pond on occassion to scoop the pond floor clean.
The big taro on the left is on the shelf in the pond.
We just move the rocks to plant the plants on the shelves.
some plants are in pots and some are planted bare root.
The lotus (next to the dock ) is planted in a pot in the ground close to the pond.
This photo is from 7-27-09
Notice there is no liner showing on the edges, the shelves go down about 12" below ground level. You do use more rocks that way, however it is a very natural look.
The one waterfall running in the back is the one we run 24/7 365 days a year.