Help with my filter, please.

[shakaho]

I'm building a new pond in my screened pool enclosure. It's a tight space, so the pond will be 400-500 gallons. I have a 30 gallon drum for the filter. It's currently soaking to remove any residues of the "Fragrant Foam" used by the car wash. My new filter is a Laguna max-flo 600, which takes 3/4 to 1 1/4 inch tubing, and I expect you will advise me to use the largest.

I've studied all of the filter plans, but still have a few questions. Hardly anyone talks about getting the water into the drum. Pictures indicate some just take the hose over the top, and others go through the wall of the drum. I'd like to go through the wall. I have a 1 1/4" bulkhead fitting (threaded on the inside). I don't have my tubing yet. What kind of adapter(s) do I need to attach my tubing? (Please understand, I am a total plumbing moron.) What diameter PVC pipe do you recommend for my down pipe and swirler? I know Koiguy used 1 1/2 inch, and others used something that looks smaller.

My husband has a blowtorch and will be happy to aim it at the wall of a drum, but how do I flatten it once it softens? By any chance would my clothes iron work for heating and flattening it?

What should be the relative height of the hole bringing water into the top of the drum and the outlet?

If I measure the minimum length of tubing I need to get from my pump, across my pond, up the side of the pond and to the entrance of the drum, how much "ease" should I add to get the total tubing length?

I promise I will have more questions, but this is a start.

 

[addy1]

Did you read the stickies? I have glanced at them, they seem to have a some step by step building instructions, not sure if it will answer all of your questions.

 

[shakaho]

I have read them, printed them out, studied them, drawn out the diagrams, compared the different versions. Like I said, I'm a plumbing moron.

 

[DrDave]

Go to my web page and look at the photos of the Doc Bio Filter. You should have your questions on feeding it put to rest after seeing these.

 

[shakaho]

OK, inside the drum I see a white pipe somehow attached to a black fitting on the side of the drum. I don't know what that black fitting is, how it is attached to the white pipe inside, and what is on the outside of the drum and how the tube from the filter attaches to that. It looks in the picture that the inlet opening is at about the same level as the outlet, but it's impossible to tell for sure.

I understand that this stuff is self-evident to you guys. I understand the biological filtration process. I have no problem with what to do with the water once it's in the drum, I know how I will support the media and what media I will use. What I don't know is how I get from the pump tubing on the outside of the drum to the horizontal pvc pipe on the inside.

 

[DrDave]

You mentioned bulkhead fittings in your post, I thought you would know one when seen. That is on the side. It is fed with a 3/4" PVC pipe that has a barbed fitting that mates with the flex tubing attached to the pump.
So you have your pump, then flex line, then barbed fitting, then 3/4" PVC, the bulkhead fitting, then 3/4" PVC inside the drum going to the bottom where you have a tee and PVC formed to cause a swirl when the water enters at the bottom.
Along with the pictures on my site, it cannot be made more clear than that.

 

[shakaho]

Thanks, that helps. I can envision what the structure has to be, but I don't know what you call the pieces. "Barbed fitting" -- that's something I can ask for or search for on line.

I'm going out to HD/Lowes to see what I can find.

 

[Shdwdrgn]

I just picked up fittings today to hook up a pump, so let me see if I can describe the pieces I am using...

First, the hose is a ribbed blue/black hose used for swimming pools. It is very similar to a vacuum cleaner hose, except its rated for use in water. You want to use at least a short length of this from your pump to where your solid pipe starts, so that the flexibility allows you to easily pull the pump out of the water. If your largest pump connector is 1-1/4", then that's the size of hose you need to get.

For the pipe going up to and inside your filter, you would probably be best using 1-1/2". Any elbows should be the longer style (called 'sweep' or 'street' elbows) so you don't cause any extra restriction. There is no difference in effectiveness between taking your pipe through the side of the barrel, or up over the top, it's just a matter of what works easiest for you.

To connect the flexible hose to your pipe, you will need an adapter. I am using a bushing (it looks like a plug with a threaded hole through the center, and fits into the wider end of an elbow). You can find one that adapts between your 1-1/4" hose size, and fits into a 1-1/2" pipe. The second piece will be found with the dark-grey pipe fittings. It will have the 1-1/4" threads on one side, and have a barbed fitting on the other side that will push inside the flexible hose.

Hopefully that helps more with how to hook up the pipes. You also asked about using an iron to soften the barrel... I doubt that will work, the torch would give you better control of the heat without actually melting the plastic. As an alternative, many of us drill a couple holes near the top of the barrel, and use something like the bulkhead fittings to make a pour-spout out of the top. Again, the final solution will not affect your filter, it's just a matter of what works for you.

 

[koiguy1969]

Aside of increasing flow capabilities, larger pipe decreases the pressure and speed the water leaves your swirl pipes..thereby minimzing the filters bottom or "sump area" turbulance, allowing a quicker settling of wastes. the longer fish wastes and debris are allow to stay in suspension the further up into your filter media they can travel. you want them to collect on the bottom to be flushed out, not stay in solution and possibly make it back into the pond as fines and DOCs.(dissolved organic compounds)

 

[shakaho]

@Shdwdrgn:Swimming pool hose is REALLY easy to find around here. There are more pool stores than grocery stores. I'll check that out.

So this will connect my tubing to the bulkhead. Inside I will use a reducer bushing to get to the size pvc pipe I'm using and then a thread-to-slip adapter to fit my pipe.

So if you heat the wall of the drum with a torch does it just flatten as it softens? If not, how do you flatten it?

@koiguy: My husband is a theoretical physicist/applied mathematician, and one of his specialties is turbulence. So I drew him a diagram of the "swirler" and ask him what effect the diameter of the pipes would have on the settling of solids. He said just what you did. Fortunately, he was busy so I got away before he wrote any equations, LOL. (Too bad he can't tell me how to get a pipe through the wall of a drum.)

 

[koiguy1969]

i bet he liked the show "NUMBERS" huh?

 

[shakaho]

You would think so, but he doesn't know anything about the kind of math that guy does.

 

[Shdwdrgn]

Sorry, I missed the purpose of heating the barrel before, I thought you were trying to form a waterfall spout at the top. If you are trying to make a flat spot to mount your pipe through, I think the easiest thing would be to get a couple blocks of wood. Heat up the barrel, then hold a block on either side for a couple minutes (possibly having someone else run cold water down the side) until the plastic cools off and holds the new form.

 

[DrDave]

A propane torch or heat gun can be used to warm it up, becareful not to burn it.