Putting Lava Rock in a filter

[Lawrence of PA]

Otter,  This is a real lesson in taking pictures that illustrate well    The waterfall bucket is buried to within a couple inches of the lip.  It's about 2 ft in diameter and 13" deep, so it's between 20 and 25 gallons.  The block of ice & lava rock was HEAVY!  The following pic shows the waterfall, the middle pool; and the reflection of the shed and the ugly orange chiminea is from the surface of the main pond.  In the foreground, in front of the waterfall bucket, is the ice & lava rock block.  It's still thawing!  The reason it freezes is that the mound that was built for the waterfall and the middle pool have huge blocks of limestone in them, and not much soil.  The waterfall mound is actually almost 5 ft above grade.  So it's pretty exposed to freezing conditions.

I was talking to my wife, who is in Paris taking French (what else? ) for a few weeks.  We use Skype to keep in touch, and I was telling her about my travails with spring cleaning.  She asked, what would you like to do?  I said, What I'd like to do is put in a Savio.  She said as soon as she asked her question, she could see my eyes light up.  I guess I'm pretty transparent. 

Larry

[Otter]

I was talking to my wife, who is in Paris taking French (what else? ) for a few weeks.  We use Skype to keep in touch, and I was telling her about my travails with spring cleaning.  She asked, what would you like to do?  I said, What I'd like to do is put in a Savio.  She said as soon as she asked her question, she could see my eyes light up.  I guess I'm pretty transparent.

LOL.  I completely understand. 

Will you insulate the Savio from the limestone so that it can run year round, or is this not practical for other reasons, or just not of interest?

[Lawrence of PA]

The previous owner ran the waterfall through the winter.  Because the pond is only a little over 3 ft deep, I'm not sure that's the best plan.  Since the pump just discharged into the top of the waterfall, it didn't really matter that the dumb thing was a solid block of ice under the surface. 

My real concern with running the water all winter is that the middle pool doesn't simply spill to the fish pond.  It has a stand pipe in the middle, made of 2" PVC.  So if the PVC ices up, the middle pool would overflow.  It might overflow to the fish pond, or it might go somewhere else while the pump empties the fish pond down to the pump suction.    I'm going to re-do the waterfall and the middle pool this spring, and then I'll be able to make an intelligent (?) decision on running the pump all winter next year.  I really do love this pond.  It was a big part of our decision to buy the house.

But now it's a project  .  Heaven knows I need more projects!

Larry

[Otter]

I understand.  I got into ponding because we bought the house next door for Mom and it came with a (badly designed and horrifically executed) pond.  I'd always thought it would be great to have one, but I doubt I'd have ever taken the time if it didn't sneak into my life as a family obligation.  I'm very glad it did.  But if I had started from scratch, I'd have done a lot of things differently. 

[Master Pond Builder]

Just increase the amount of filter pads just under the maximum that your water fall filter will hold. There is far more surface area for bacteria to colonize in the small pores of these filter pads than in any type of gravel. Maintenance will also be a breeze because you do not have a heavy bag of rocks to deal with. Just make sure you hold the pads down with a couple of larger rocks as they will float otherwise.

[Bearb]

I'm a bit late to the party, but I thought I would share. . . For bio-media, I have been using plastic bottles from my recycle bin. I cut the spout out, then make a long spiral cut (on the bottle) until I reach the bottom. I end up with a very long "ribbon" of plastic about 1/4" wide. Then I coil it up into a loose ball (since it is really a long slinky like spring of plastic, this is easy) then I zip tie the bottle spout in the center of the coil, fluff it up a bit and it is all done. I end up with a ball about 3 inches that sinks. I like the bottles with the smooth sides (like 2 liter soda bottles or the straight sided water bottles) because they are easier to cut.

[jw]

RWinn, What kind of hair curlers do you use?
                                            Janice

[casey]

Bearb,

I thought bio filter media had to have pockets for the bacteria to colonize in it.  I didn't think something like a smooth sided plastic would work because there is no place for the bacteria to attach.  Explain this to me so I can learn more about bacteria and how they colonize.

Casey

[Otter]

It's true that  highly porous media have many times more surface area in their pockets than you get with nonporous media, but those pockets plug up and become anaerobic.   This is great for getting rid of nitrate because the bacteria are forced to break down nitrate into nitrogen and oxygen, but to process large amounts of ammonia and nitrite, bacteria need plenty of free oxygen.  Bacteria have no problem growing on flat surfaces, and all they need to process ammonia and nitrite are oxygen and somewhere to grow.  Hence, nonporous plastic works quite well in a biofilter, as long as you have enough of it.  Maybe ceramic media still have more aerobic surface area than potscrubbers or shredded water bottles, but as long as you have the space for lots of plastic, it gets the job done at a fraction of the cost.

[Bearb]

What Otter said. . . this has (I'm sure) a lot less surface area, per cubic feet of media, than the fancy stuff but it is free and easily rinses off each spring. I have a small skippy type bio-filter and top it off with water hyacinth and sweet potato vine. I must have enough space to make up for the inefficient packing because it never blinks. I also made a simple venturi so I have plenty of aeration in the filter (this also stops the filter from draining when the pump is turned off). Sometimes I wonder how effective the reported surface area is on very porous materials; I question how well oxygenated water flows over the deepest nooks and crannies.

This year or next, I will be expanding my pond and may find that I need more space for media. I kinda doubt it (in the short term) since the fish load and flow rate will be the same just more water. Any thoughts?

[casey]

Thank you Otter & Bearb,

This forum has so much to offer and I appreciate the time you took to teach me something new.

Casey

[Otter]

This year or next, I will be expanding my pond and may find that I need more space for media. I kinda doubt it (in the short term) since the fish load and flow rate will be the same just more water. Any thoughts?

I think you're probably right, Bearb.  If you have trees, more surface area will mean more leaves, and maybe a higher percentage will stay in the pond because of the reduced flow.  That could increase load.  Or your fish might grow bigger.  Or you might have twice as many tadpoles.  But if the total load stays about the same, I don't think you need a bigger filter.  OTOH, if you're expanding anyway, you might want to dig a big filter pit.

[Bearb]

Don't get me started on trees/leaves, though I think the increased surface area will mean increased maintenance rather than load. . . You make some good points! The expansion is inspired by increased fish size and population. I ended up with more liner than I need for the space I have. I have been trying to figure out how to make best use of it. You've go me thinking about digging a hole to replace the container that currently holds my media, or maybe adding a bog. Well I guess I have more research to do. Thanks a lot Otter.

[Otter]

Ponding is a good workout for your brain, eh?

[Bearb]

Let's hope that the more workout my brain gets, the less my back will get come dig time .

[frloplady]

Otter,  This is a real lesson in taking pictures that illustrate well    The waterfall bucket is buried to within a couple inches of the lip.  It's about 2 ft in diameter and 13" deep, so it's between 20 and 25 gallons. 

What your waterfall bucket was really made for was for a watergarden made with whiskey barrels..that is a liner that drops into the barrel.  I got one too!  With a uniseal you could put a hose into the side of it and a drain in the bottom, but there are other things that would probably work better.  Lots of nifty DIY filters that can be made with 55 gallon barrels and hide them behind a waterfall berm kind of thing

edit: I forgot to add my 2cents on filter media.  Have used lava rock..works well, a bugger to clean.  I've used floor scrubber pads for mechanical but they also serve as bio.  I've not used matala mats yet, but probably my next thing I'm going to try.  Dollar store shower scrubbies.  They rinse relatively easily and MUCH easier on the hands than lava rock!!

I bought dollar store curlers before but felt there wasn't enough bio surface for the space it took up.  People with lathes have made pvc shavings off a pvc pipe.  Not to be done by the inexperienced I've heard.
The white strapping tape that is used when shipping boxes...a lot like springflo but MUCH cheaper.  It has to be weighed down in the filter as it likes to try and escape once it's squeezed in.  That with an air blower manifold under it to help clean..another project for this spring that I hope to get done by next spring 

Sand/gravel filters..not only good fines filtration, but makes a pretty decent bio filter as well.

Mary

[oldgeezer]

Lava rocks in waterfalls are highly recommended. I have them in 2 pond waterfalls. Good bio action and no downside that I have heard of. Be sure to flush before using and cover with a some larger stones to prevent loss into pond.