DIY External Inline Co2 Diffuser

[IUnknown]

Got my order in today, but ended getting some fittings that wouldn't work. This is the updated parts list, but I would hold off until I get them in, just in case.

This is for 5/8" tubing (16/22mm eheim). If you have a smaller canister filter (12/16mm) you would need the 0705T.028 (5/8" to 1/2" reducer).
0710T.028 5/8"elbow (2) $.88
6030.010 1/2" Mazzi injector $22.05
5041N0.05 1/2" Ball Valve
1435.005 1/2" Female hose adapter (2)
0700T.195 1/2" Male hose adapter (2)

I'm going to see how much of this stuff you can get at a hardware store. I usually order from ryah herco, but I'm not sure if they are a wholesaler only? I just put a company name down and say "verbal" when they ask for a PO number.

OK forgot to mention the TEE's on the last post,
1401.005 1/2" insert tee

Got all the parts in, going to test it out this weekend. Doesn't look very pretty.

OK, I really like how the Mazzi injector worked out. The tank gets showered with Co2. I'm scrapping the ball valve design, and like Tom recommended, adding another pump inline to my canister filter output. This setup will look cleaner, all you'll see is the Injector "Y" into the outlet pipe.

The ball valve cut too much flow from the canister. If anyone has any ideas on what kind of pump to select, let me know. Maybe like an eheim 1048 (80 gph @ 3' $50). Or a mag drive (160 gph @ 3', $40) to match my canister flow rate (eheim 2224, 184 gph). What effect does restricting the output on the pump have?

IUnknown - Photobucket - Video and Image Hosting

 

[IUnknown]

OK, so I tested things out and I made a mistake by sizing the pump at the same flow rate as the canister filter. Mazzei's website states that the pressure difference needs to be at least 20%. So I returned the pump and replaced it for one that will do 600gph to hopefully create the difference in pressure. Now the other question I have, if the booster pump is doing 600gph and the filter is doing 200gph, would I place the intake for the booster pump on the outlet of the canister filter (like my diagram on the previous page) or on the intake of the canister filter? I guess I can test both options, keep the outlet flows separate, and see which method keeps the flow to both pumps stable.

Also the other mistake I made was that I put the injector right below the lillie pipe. Maybe I need to put it right after the pump like on Mazzei's diagram,

Mazzei Injector Corp. - Selecting an Injector

 

[Professor Myers]

I Like It !

definitely closer to the pump though. That allows for higher static pressure, and greater contact time, and saturation. A dedicated pump would help. The Mazzei injectors are about the best in production.

Update: I just noticed, Do you have the venturi, and ball valve transposed in that configuration ? Shouldn't flow control be on the main line to direct pressure to the Venturi valve ? Never mind me I'm just curious by nature ! ;^)

 

[Professor Myers]

In your 1st. photo...

On your original configuration try swaping out the Ball valve and Venturi. Also reverse the two sections of hose on the bye pass end for end. Short section+Venturi+long section. Then re-adjust the ball valve till you begin to draw gas. Again, placing the whole bye pass assb. closer to the pump may improve line pressure. If you're not seeing enough bubbles entering the tank place the assb. next to the lilly pipe. Depends on whether you want disolved Co2 or micro bubbles. HTH. Prof M

P.S. which model Mazzei Venturi are you using ?

 

[VaughnH]

Won't the return flow from the booster pump act as a big resistance to the filter flow trying to get by the blast from the venturi output? I would expect to see the filter flow drop close to zero and the booster pump primarily recirculate the same water over and over. If you used an elbow similar to a "sanitary elbow", with the side passage entering almost parallel to the main flow it would work much, much better. The venturi line flow would actually boost the filter flow then.

 

[Professor Myers]

Yup !

That it will ! I'd also increase the output to a corresponding larger size. If I were using a secondary pump I'd just run it dedicated. That venturi valve will only handle a few hundred gph.

 

[Tom Barr]

Nice layout and pics.

I think the issue here is really the size of the tank, it's just so small vs the expense for a 20 gal tank.

Fine for experimentation though............

The cost of the glassware is 10-70$ depending on the brand.
I'm trying out some of the Japanese knock off brands to see if they are better than/equal to the ADA beetles.

I have some very small and some very large tanks.
Each has it's own issue.

The 1600 gallon tank has the venturis and the disc.
The disc send visible mist through the tank and create a large froth with proper placement of the outflows and disc.

While I have 1.5 gallon tanks that have issues with getting something small enough to not be too ugly.


Regards,
Tom Barr

 

[Tom Barr]

The needle wheel powerheads are also about 40-70$ as well and be used inline in some applications.

The impeller runs 15$ and can be used in a Rio 2000.

Big powerhead really, maybe they will make small ones later.

 

[Professor Myers]

That's about the size of it, Tom

"I think the issue here is really the size of the tank"

The biggest challenge is properly sizing the volume, and metering the Co2 to accommodate the application.

 

[Professor Myers]

Does he need a pump ?

I honestly believe that if the bye pass is properly configured his present canister is more than sufficient, albeit a bit large for the tank.

 

[Tom Barr]

Yep, but this is not about the $$, while still considerable less than a Pollen Glass 20 mm etc and more than likely more effective.

I think it will appeal to folks that do not enjoy stuff in their tanks, like in line devices, are more interested in the mist effects vs the 100% dissolution methods reactor tubes provide.

If you have used disc and blasted the mist around with current, you can see the long term and short term growth differences vs other parts of the tank, the goal with such mist devices is to how best distribute them.

Venturi's and spray bars appear to be one of the more effective methods.

Regards,
Tom Barr

 

[Tom Barr]

BTW, here's a new photo of the tank, I redid many things this time and it should be left alone for the most part.

The client is going to add 100 Erio's(Bare spot on right hand side), 50 dowoni(a little towards the middle), some Bolbitus(on some wood on the middle and right sides), and more HC in the front.
I think removing some Crypts and replacing with Lobelia will also look a bit better and not be a hard to prune as the Green Rotala.
Hard getting all the plants you want when you need it.

From there, it is a prune and wait.

 

[Professor Myers]

"sanitary elbow"

RE: "sanitary elbow" You make a significant point. I'll try a radiused turn from the venturi, and a sanitary elbow to merge the line. Can't hurt ? I'll note any difference in flow, and mist.

I'm testing a 1/2" at a dedicated 187 gph. I'll run it straight, and then attach the bye pass. One thing I figured out today was my old Eheim 2217 Classic pushes twice the head pressure of the 2224. Of course the 2224 draws 8W and the 2217 pulls 20W. Apparently that efficiency comes at a cost ?

 

[Professor Myers]

New photo

Alright ! I'm actually jealous...Doesn't happen very often. I don't have the space these days for any more large tanks. Prof M

 

[IUnknown]

Update: I just noticed, Do you have the venturi, and ball valve transposed in that configuration ? Shouldn't flow control be on the main line to direct pressure to the Venturi valve ? Never mind me I'm just curious by nature ! ;^)

On the Mazzei website, they show it how you describe. I thought I had tested that configuration and had no luck. I'll try it again this weekend. I'm using the Mazzei model number 287 (1/2"mnpt, 3/16 suction port).

VaughnH- I guess I can test that when I start getting mist and see inside the clear tubing if the mist is going back into the booster pump. Another person brought up the thought that maybe hobby pumps are not engineered to deal with pressure in the line. But having the injector right after the pump would probably help.

Tom-Yeah, I saw the picture that you posted. Looks great. Love the contrast of the color of the green and the wood paneling. Can't wait to see it with all the fish in. I'm sure the zoo is going to be sold on the project. I think everyones cheering for you Tom, the hard work shows.

 

[Tom Barr]

A nice low flow venturi seems like a wise idea.

IU- I'm heading to Albany to redo the 125 for Guy this SAT.
I've never used the African root in any scaping before, but will this time.

I recently got some Aquaticmagic.com ADA beetle knock off diffusers, the 1000 and the 5000's.
10mm and 50mm basically.

You can check out the effectiveness in the coming weeks with good flow and the mist method.

I suppose the tank is big enough to add a 3/16" venturi cheapy Kent.
I'm going to do all disc though, the set up is perfect it for it and the tank has lots of plants for scaping very close by

The AM disc seem to be every bit as good as the ADA stuff but about 4-5x cheaper.


Seems like if you could have a little bubble chopper like the needle wheel thing/ides but driven faster by flow rate, that might be better for low flow applications than venturis.

No pump, just a drive system that spins the chopper impeller wheel around, that would not take much energy to zip the speed of the impeller fast.
The constriction from the venturi does drop the flow down considerably.

That's the rub with the darn thing.
I use 2 seperate large powerheads for the large behemoth.

On future Zoo exhibits, we will use venturis and disc, the mix gives the desired results like a 20 gallon tank in terms of getting enough CO2 in there fast, great response time.

Larger tanks are a bugger to get enough CO2 with high lighting.
I know I've solved that issue now so I have no problem doing anything massive. If you control the CO2 effectively, then the rest is easy, dosing/lighting/water changes etc.

Massive planted tanks in the Zoo's will be awesome.
BTW, Tenji, the group I work with for the engineering is doing a lot of the Steinhart tanks in SF's revamping of their Aquarium.

Mark might have me do some of the work there.
We will see.

I have the wood, I have the rock, I have the CO2, I have the lighting, I have the soil, I have the routine/dosing/ferts, I have the plants.

Not much else will stop me from promoting planted tank world domination

If those in power have them and like them, then the rest will follow.

Regards,
Tom Barr

 

[Professor Myers]

Low Flow Venturis

Seems like common sense now, but VaughnH's observation of of the T inlets is actually pretty significant. Given the restriction of flow all those 90* turns add up quick ! The bye pass is text book, but I don't think that book covers power heads, and mag drive pumps ?

I did recently discover that Mazzei already offers a selection of precision machined stainless steel drop in ports for gas injection venturis. This is good !

Of course I also discovered that the 2100, and 2700 needle wheels are on back order, and the smaller Ocean Runner Pumps are hard to come by. This is Bad !

Then I discovered that the needle wheel pumps for the Super Skimmers can't supply an adeqaute line pressure for remote placement. This is VERY Bad since Coralife appears to be the only source of needle wheel pumps that has even the slightest chance of hitting their @$$ with two hands and a catchers mitt !!!

Difficult to spec a product that can't be supplied ??? The Ocean Runner pumps are good, but if any one knows of any way short of dynamite to motivate their salesmen, Please by all means do fill me in on it ???

The Kent Venturis arent bad. They're not quite as nice as the Mazzei, but they're a good value, and Kent's VERY Reliable. I'm finding out that Reliable counts for alot more than any feature at this point.

 

[Tom Barr]

Rather than constricting the water flow, think about making the inlet for the gas smaller, much smaller.

We do not need large violumes of gas right?
Generally that is what the venturis do, add lots of air.

Bubbles per second, maybe up to 5-10 at most.

A tiny inlet in the tube for gas will also produce a tiny bubble.

Regards,
Tom Barr

 

[VaughnH]

An inexpensive venturi with a microscopic size orifice for CO2 at the throat sounds like it would work great - for a short time. Then the orifice would plug up. But an inexpensive venturi with a CO2 port having a very small limewood, for example, difuser in the end might work for a substantial time. On one of the forums a poster was promoting the idea of using short pieces of chop sticks - bamboo, I assume. That might work well too. The goal should be, in my opinion, to have multiple microscopic orifices, so until the last one plugs up you still have CO2 mist being generated. I can't see myself doing this experimenting, but I hope someone does.

And, it won't be at 10 bubbles per second, with such small bubbles, but more like 100 per second. That suggests that it would take multiple parallel orifices to allow that much flow.

 

[Professor Myers]

Gas Intake

Sourcing the Venturis, Pumps, and impellers is only a consideration of convenience. Won't do much good to supply a simple process, if the parts themselves are exotic.

I'm focusing on the gas intake for now. As far as constriction goes you can actually go from a 5/8" barb to a 3/4" npt venturi and still supply adequate pressure if the gas intake is appropriately sized. So far this has been the simplest application with my Eheim 2217 canister.

Mazzei's drop in ports do go down to sufficiently small sizes, and only cost $2.50 USD, but the cap tubes work really well, and If I can cut these with a laser, labor is trivial, and 300 tubes will cost $6.70 USD, and the 1/8" bulkheads are $2.25 USD.

While I prefer the Mazzei injectors folks can buy the Venturi of their choosing screw in the metered bulkhead, and adjust the Co2 flow rate until their tank looks like a glass of Club Soda ! LOL. If it's stupid and it works, is it still stupid ??? Grtz, Prof M