Misting with a Mazzei - Questions and Observations

MISTING WITH A MAZZEI: QUESTIONS AND OBSERVATIONS

I'm writing this because when I was looking for a Mazzei injector to buy,
I had some questions that I couldn't answer until after I had already made
the purchase. Also, there is not a lot of specific information regarding the use of
a Mazzei injector for co2 injection online.

Here are some questions and observations I had when using a Mazzei venturi injector for the injection of co2 microbubbles into a planted tank:

I have a quietone 3000 pump running a lifeguard mechanical filter module on my 29 gallon tank. The micron pleats have been removed from the cartridge within, and replaced with quilt batting from walmart. This really increased my flow and freed up some gph that I could use to run the mazzei. The quietone 3000 has 780gph and 10ft. max head. According to the pressure gage on the filter module, the pump can push a max of 5psi, and the entire system only generates about 1-1.5 psi of backpressure (from head loss, filter floss, tubing).

The performance tables from the mazzei website give specs like the amount of water that can flow through the injector at a given psi, and what suction will be created given different inlet and outlet pressures on the injector.

I really couldn't decide between the model 584 and 684. The 684 can handle more flow through it but might not create a good suction or create a very fine mist of co2, suitable for co2 misting in the aquarium. The 584 creates higher suction at 5psi, and from numerous posts I read, generates a really fine mist - almost too fine. But I thought that it would restrict the flow too much - more than the 684.

I found numerous cheap sources for the 584 and 684 models. The 584 came with pipe threads while the 684 comes with hose barbs. They cost 35-39 dollars plus shipping. If anyone wants the names of the online places I found, please feel free to PM me - these were the cheapest I found on the internet after hours of exhaustive searching - that were still genuine name brand Mazzei products. Off brands can be found for cheaper, but I have read that Mazzei's are machined very precisely and are of the highest quality. Both of the models have 3/4" barbs/threads. There IS the 584-C which has 1/2" threads but is the exact same size & dimensions as the 584.

I decided to buy the 584 model because: it came with 3/4" pipe threads that I could either attach 1/2 or 3/4 inch hose barb fittings onto, depending on where in my system I decided to place the injector. That and from the very few threads regarding the subject, I knew that it worked for the other people that used them. I have not seen anyone that has claimed that they have used/purchased the 684 model. I really wanted to try it if I had more $$, but I knew that at least the 584 worked for creating a great mist of co2 in the tank.

Before I hooked the injector up, I was holding/looking at it. I noticed that when I blew hard into the injector in the direction that the water was supposed to flow through it, there was almost no resistance and I could feel the suction with my finger over the venturi/suction port. When I blew through it going the opposite way the water was supposed to flow, there was noticeable resistance to the air. It was really interesting to see how one direction was made to offer as little resistance as possible, while it was not true for the opposite direction.

Here is how I hooked it to my system:
The pump outlet goes to a ball valve to the filter module to another ball valve. From the 2nd ball valve is about 3ft. of 3/4" tubing which connects to a hose barb that I screwed onto the INLET side of the Mazzei. The OUTLET of the Mazzei screws into a T fitting. The T splits the water into 2 half-inch tubes about 1.5ft. long that flow into the aquarium. The output of the Mazzei feeds directly into these 2 tubes that go into the tank. The suction/venturi/co2 port is .25" OD. It is hard to fit a standard airline/co2 tube over this. But, a piece of rigid airline tubing fits perfectly inside the port. I attached my co2 tubing to a small piece of this rigid tubing and slid it into the suction port.

I turned my pump on and.....the Mazzei works FANTASTIC. It fills every square inch of the tank with a mist so small, it looks like dust. And the bonus was that IT DID NOT AFFECT MY FLOW. According to the pressure gage on my filter module, the addition of the mazzei venturi injector inline with my filter outflow only added maybe .5psi of backpressure. The loss of flow is negligible. I DID notice, however, that flow does decrease if the co2 suction port is just wide open to the air. It pushes large bubbles of air through the tubing and it slows the flow of water through it a lot. When I put a finger over the opening and just let the air barely "hiss" into the injector, the bubbles that are produced are extremely fine and the flow through the Mazzei is not really affected. So, I think the size of the hole INSIDE the injector, in relation to the water flowing through it, determines the amount of suction created at the gas inlet. But the amount of gas/flow of gas through the co2 inlet determines the size of the bubbles/mist. Higher suction at the gas inlet can handle a larger amount of co2 and still produce a fine mist. If the water pressure is just enough to create a small suction, the gas flowing into it will need to be controlled/restricted. If too much air/co2 is allowed to be pulled into the Mazzei, large bubbles will be created at these lower suction rates. This is the case for me. If the port is wide open, or the bubble rate of my co2 is too high, larger bubbles/mist will be created and my flow will diminish. I have tried to heat the rigid airline tubing and slowly pull it out (like hot cheese on pizza). This, with practice, can create a long taper with a very small hole at one end. Then I pushed the end with the small hole into the suction port and attached my co2 line to the other end. This works fairly well, but the rigid tube can become misshapen by the heat, and not fit snugly and exactly into the Mazzei. I also tried using a gang valve. By hooking the co2 line to the gang valve and then to the suction port, I can use the knob to barely crack open the airway and let the co2 "hiss" through.

That should be it regarding the setup and operation of the Mazzei injector, but there are still a few problems I am trying to figure out. When my rigid tube was misshapen and was not fit snug into the gas inlet port, air was able to "hiss" into the injector, as well as the co2 coming from the tubing. The addition of oxygen to the mix kept my tank very well oxygenated at night, and caused EXTREME pearling from every single leaf in the tank during the day. But during this time I had problems getting the drop checker to read the yellow-green that I know I need. So even though fantastic misting and pearling was evident, co2 levels were insufficient.
---Is this because the co2 was present as mist vs. dissolved in the water?---
------OR--------
---Is this because mostly air was being drawn into the injector and the co2 was escaping through the leak in which the air was being drawn?---

Using the gang valve I wanted to have one valve barely cracked open to the air, and one valve open wider to the co2 tube. Thus when the co2 is off, only air is drawn in for the plants at night. And when the co2 turns on, since the opening is wider to the co2, I thought the co2 would be drawn in more/faster than the air (or at least a mix of both), but I would still get a nice mix of o2 and co2 to facilitate the mist production and keep o2 levels up for the fish/shrimp.

I have decent surface movement and a surface skimmer, but have only witnessed satisfactory pearling when I have oxygenated the tank water with an airstone, or more recently the Mazzei.

Both ways of trying to get the mix of air and co2 have produced good pearling (due to the forced oxygenation of the water) and heavy mist in every square inch of the tank (also due to the air) but poor co2 levels as indicated by the drop checker. Algae is also creeping in, as well as melting stems/leaves and other co2 deficiency? symptoms.

When I make a direct connection from the co2 line to the mazzei, with no air leaks, gang valves, etc., I get a better co2 level according to the drop checker, but a LOT less mist and a LOT less pearling (because air/o2 is no longer being injected). I DO NOT know why I only see pearling this way. It's not bubbles sticking to the leaves, I'm positive. This seems to be "cheating" to get pearling, and it confuses me as to why I am observing the pearling in this manner.

---How do I get the best of both worlds?---
---How can I inject air and co2 during the day, and air at night?---
---What is the best way to attach the co2 line to the suction/gas port?---
---How can I get a bunch of co2 mist without having to use a huge bubble rate?---
---How do I get high co2 levels without having to pump the bubble rate to >4-5BPS?---

 

--continued from previous post--

I don't think the air is degassing the co2 INSIDE the Mazzei injector. I don't think it's being lost (significantly) at the surface of the water/tank. I don't think I'm losing co2 because of the surface skimmer (I had good levels using the RhinoX diffuser and the skimmer). Could I have TOO MUCH surface movement? The drop checker returns blue/blue-green at night a LOT faster than it takes it to reach a yellow-green in the morning. This is really the only other place besides the Mazzei suction port, that comes in contact with air/oxygen. But I don't really think too much surface movement is the problem, again because things were working fine before I added the Mazzei. The surface quickly ripples across the entire surface from the lilly pipe, but the surface tension of the water does not break. Neither is there any splashing or turbulence in the surface skimmer tube. Nor is the surface tension broken in the skimmer. The water glides down the throat of the skimmer for only an inch or so to the water level inside the tube. What's the deal?

Anyone have any tips for increasing the efficiency of these Mazzei injectors? Or any tips in general for using the Mazzei?

I really need to figure this out because I'm starting to see BBA and have a lot of melting leaves and stems that I assume are due to the inadequate/fluccuating co2 levels during this week that I have been tinkering with the injector. I'm mad because I thought I could increase the mist in the tank by using the Mazzei, and its obvious that I can, but everything was humming along just fine before I made the change. I was using the RhinoX 3000, and getting great co2 levels and ok mist, but I hated it being in the tank, and I had to clean it all the time to keep it working properly. The Mazzei is definately the way to go. It can produce TONS of mist, it can quickly drop the ph, it is OUT of the tank, and when appropriately matched to the size of the filter/pump - doesn't really diminish the amount of flow into the tank or cause an increase in the backpressure of the plumbing. Mazzei Corp. even makes really small injectors that could be used on smaller tanks, given the tank has an appropriate pump, tubing, and fittings. There are also many way they can be plumbed into the system to get required pressure differential across the injector. The Mazzei website has pictures of these setups, as well as performance tables for each model of injector. Their webpage is: http:\\Mazzei Injector Corporation - Fertilizer and Chemical Injection, Wastewater Aeration, Ozone Systems

-Mike B-

 

Update Dec. 5

UPDATE:

I decided to keep the Mazzei hooked up using the gang valve. Instead of the gang valve splitting one airline into two, I have the two lines joining into the one that leads into the suction port of the injector. One line comes from the co2 regulator and attaches to the gang valve. Since the co2 is only being released at about 4-5bps, it is a very small amount of gas at a very slow flow. Thus I have the gang valve opened all the way for the co2 line, and the injector still produces a fine mist. The other valve is used for air. If this valve were open all the way, the Mazzei would suck in too much air and create large bubbles and slow the flow of water through it. So, this valve is just cracked open ever so slightly. The injector can barely suck air through it, and most of the time it looked like the Mazzei wasn't pulling ANY air through it. A blast of air mist was only produced very 30 seconds or so. This wasn't enough for me, so I hooled an airpump to this valve. It helps push air through this tiny opening and keeps the mist it creates constant. So, a small stream of air and a small stream of co2 are being pushed into the gang valve and combined into one single line that feeds the Mazzei. I have the co2 at about 4-5bps. My drop checker reads a yellow-green, and I get a good, fine mist of co2 and air during the day, and a mist of just air at night. This really helps me worry less about adding too much co2 and suffocating my fish and shrimp. I also don't think that adding air in this manner outgasses any co2. Both lines feeding the Mazzei are under positive pressure and are not open to the outside. If I'm just fooling myself, somebody please let me know. This seems like the perfect method, but in real life things rarely are. However, I do really like being able to "shoot" a mist of air and co2 deep into the tank and plant beds. I can also see the current and flow patterns in my tank by watching how the mist moves around. It shows where and how fast the water is moving. I love it, but also think that it makes the water look slightly cloudy from a distance.

I did a big trim in the tank, and curiously I'm not seeing the massive pearling any more. Even from the plants I didn't trim, like the crypts. The moss and crypts used to pearl heavily (as well as every other plant) when I first started experimenting with the Mazzei, but over the past few days it has stopped. Maybe the plants were limited in something that was "unlocked" when I installed the Mazzei, and they grew vigorously for a few days and are now "all caught up", and now they are back to growing at a normal rate. I have no idea at all. I'm just guessing.

Please, I would love to hear other's observations of their plants right after installing a Mazzei. How did you set up the Mazzei? Did you witness abnormal pearling? Did it stay or go away after a few days/week?

Sorry for all the typing, but thanks for reading!

-Mike B-

 

Thanks for looking over this, Tom.
The issue of the Mazzei sucking co2 vs. backpressure building up with a glass diffuser is something that I did notice. The low pressure gage is not as responsive on my regulator, and the bubbles in the bubble counter dont seem to respond to minute changes very much either. The injector can create a fine mist up to the point that the gas is being actively pushed into the injector faster than the injector can suck it.

The bubble count I'm using with the Mazzei is almost exactly the same as the bubble count I used with my RhinoX diffuser. Which is odd, because I thought the Mazzei might be more efficient, and that I could achieve higher co2 levels with a lower bubble rate. But, the drop checker indicates that I really need about the same amount of co2 regardless of how it's delivered -- at least regarding the Mazzei vs. glass diffuser. -- Maybe because both are mist-type co2 delivery systems.

I'm starting to see really good pearling again, and I think that the reason for the sudden disappearance of it was the big trim that I did. Somehow I stunted everything and after about a week the plants are starting to grow normally again. I trimmed all the plants back and had to pull up my HC foreground and replant it - stem by stem - as it was starting to die underneath. I dont know why, and I could surely be wrong, but I think the sudden loss of a large % of biomass along with the foreground removal/replanting disrupted the tank's stability.

As for the bubbles making the water look cloudy, I'm totally wrong. The water really IS cloudy. I stupidly had already taken out a lot of the water so I could easily take out and replant the HC. I gravel vac'd the aquasoil and replanted the HC. Then I took out a little more water and then refilled. (I trimmed before I took out any water) I should have done ALL of this before taking out ANY water, and since I didn't, I think I caused an ammonia spike resulting in the beginning of green water, and/or a bacterial bloom due to the loss of the biomass & substrate disruption.

That is really for a different thread, but the point HERE is that the mist the Mazzei creates is really not distracting or detracting from tank asthetics. The mist can be seen close up, but the water still looks clear, and the whole tank looks clear if viewed from a distance of about 4 feet or more.

I'm going to try to post a few pictures soon.

-Mike B-

 

*#&^$(*&#@^$*&#@Q^$ I just spend an hour writing a huge post and accidently hit the back button a few times and lost everything I just wrote

AAAHGHHHHHHH!!!!!!!!!

ok, Mrkookm, I wasn't trying to suggest that there is much of a match between the glass diffuser and a Mazzei, just that AT THE VERY LEAST it will work as well as a diffuser. But yeah, there really is no comparison for mist production and co2 mixing.

A 384 with a large pump - creates huge suction but still produces same mixing and mist in the tank. Higher suction can allow more gas to be injected, but we dont really ever need to inject gas at this high of a rate. Also a small Mazz. with a large pump will restrict the flow of water because the orifice inside the Mazz. is very small. A bypass will have to be built to conserve some of the flow, but this will still create tubing and fitting loss on the system. A 384 on a 1100gph 28ft. head pump is way, way overkill. A huge suction will be created, but the mist it produces isn't any better than if it were produced on a 584 with the same pump.
An 1800gph pump on a 384 is SUPER overkill and would definately need a bypass, and would still have some reduction in flow.

A 384 with a small pump can still create some suction. And as long as ANY suction is created, a mixing and mist will occur - as long as co2 isnt pushed faster than the suction can handle. This will create larger bubbles which will slow down the flow of water in the tubing.

Higher suction can handle a larger volume of gas to be mixed, but doesnt mean that it will mix it any better/worse than if a smaller suction were created from either too big of a Mazzei, or too small of a pump. In my opinion having really high suction isn't even necessary because the amount of co2 we are adding is not more than an injector can handle (mix/turn into mist) at any suction. If the combination of Mazzei and pump can create any kind of suction, it will be enough to inject co2 to an adequate level in our tanks. (except maybe for really large tanks).

A 584/684 with a smaller pump can create some suction and won't have a flow loss. A 584/684 with a bigger pump will create more suction and can handle more co2 being added. This might require a bypass, but if you have a big pump, using a bigger mazzei can save you from having to create a bypass and still conserve all your flow and also create mist.

Gerry, I would use your main system pump with either a 584 or 684 Mazzei. Your pump will still be PLENTY to create enough suction for all the co2 you want to inject, will still create co2 mist, and you wont have a reduction in flow or the need for additional plumbing (a bypass loop). This is precisely why they make bigger Mazzei models. Yes a 384 would work also, and would give you great mist, but there's no need to go through all that trouble when you can get a Mazzei that is correctly sized for your pump. Put it right before your T and then you can have mist pouring out from both of your outlets into your tank. You might want to keep the reactor until you get the Mazzei working, but in the end it just isn't necessary. The Mazzei will more than handle your tank's needs and a 684 wont require any fenageling to try and save your flow into your tank. That is why I think mrkookm has a HUGE pump on a TINY mazzei on a tank that is HALF your size -- He has a tiny mazzei and needs a huge pump and a bypass just to keep the flow up in his tank. (I'm not taking a stab at you Mrkookm, , just trying to make a comparison) My 584 works great with 800gph/10ft. max head. I get all the mist I need, and even have enough suction left over to inject air from an air pump to keep o2 levels up - all the while producing a super fine mist with no reduction in my water flow and without the need for any bypass of any kind. My pressure gage also shows negligible added backpressure from the addition of my Mazzei inline - even when plumbed to the very end of the filter/tubing system. Something smaller just isn't necessary, and only serves to complicate our plumbing systems even more.

=========================================================
If I were to select a Mazzei based on my pump's stats, here is what I would feel confident in purchasing:

1. pump:0-500gph, up to 8ft. max head -- Mazzei 384 - no bypass/no flow loss
2. pump:500-1000gph, 8-12ft. max head -- Mazzei 584 - no bypass/no flow loss
3. pump:1000 and up, 12ft. max head and greater -- Mazzei 684 no bypass/flow loss

Pumps from #2 could work with the 384, and pumps from #3 could certainly work with the 584 and 384 Mazzei's, but there probably would be flow loss and a bypass loop may need to be plumbed into the system.

Like I said, mine is a quietone 3000 pump - 780gph and 10ft. max head - it pushes a max of 5psi - and works fantastic with the 584 - with NO flow loss and plenty of suction to mix gas and water, and creates a superfine mist in every inch of my tank. I also have a very "clean" setup with no extra tubing and fittings, thus saving as much flow as I can and minimizing head loss. There is no need to undersize your Mazzei to get great mist and then do all this extra work to try to get your flow back from nothing. It's just not necessary. That's why Mazzei makes different size models. To be the most efficient at injecting, while disrupting the flow/system as little as possible.

But there surely are a number of ways to hook one up to work properly, and both mine and mrkookm are just two examples. I think his is the extreme in one direction (small Mazz w/ huge pump), mine is in the middle (mid Mazz. w/ mid pump), and someone else might be at the other end (large Mazz w/ tiny pump) I dont think a tiny pump would really work with a 684 or higher, but I think its possible to have a small pump drive a 584. I have seen threads & posts of people using the 584 on canister filters, which are about half the gph and half the max head as My quietone3000 pump, and they have been shown to have acceptable results. IUnknown is one person who had a thread on TPT and APC where he finds the 384 is too small for his canister and causes way to much loss in flow, and the Mazzei engineer reccommends the 584. He gets great results with the 584, no noticible flow loss, and it is what he ultimately ends up keeping/using.

Gerry, I would still strongly reccommend against the 384 on your 180gal. tank with such a huge pump. I would have no problem using the 684 with your setup if I was in your situation. The 684 is what I originally wanted to purchase. If you can find what psi your pump makes when the output is closed off completely, then you can look at the Mazzei performance tables and fine a model that generates decent suction, but also can handle a "motive flow" that closely matches your pump's gph. This is what I did to determine that I could use the 584 and 684. It was easy since I could see my pump made 5psi and that during normal operation there was about 1.5psi backpressure in the lines at any given time. These were my inlet and outlet pressures I used to look up on the Mazzei tables. I multiplied the motive flow gpm by 60 and tried to find one that had a motive flow close to my pump's gph, and with the inlet and outlet pressures looked at what suction would be created at these pressures and flows. Then chose one that an "average" rate of suction. If you look at the chart it makes more sense.

Thanks for reading and for everyone's input!
-Mike B-

P.S. - I thought my first post was better, but hey, maybe it happened for a reason.

 

Some pics of the setup and tank:

The first shows the fittings I attached to the Mazzei.

The second shows my pump, filter, and tubing. (Can you read the pressure gage? This is the usual running pressure, the first big "tick mark" is 5psi. The needle shows about 1.5.

The third shows how high the Mazzei is placed, and the 2 tubes that come off from it and into the tank. The black stuff over the tubing is something that is used to hold electrical cords together, but I used it here to prevent algae growth.

The fourth shows the whole tank, with the inlets in the back left and center, and the outlets in the front left. The 2 outlets are .5" tubing, and the main tubing that goes from the inlet to the filter and then to the mazzei is .75" tubing.

Hope the pictures help some. I dont have a camera that can take a picture of the mist, but trust me, it's there!

-Mike B-

 

These are some of the posts by IUnknown:

Round four of testing. So I received the PC pump and computer adapter and wired it up. The pump creates a lot of pressure, but what I noticed is that the venturi has to have very little pressure on the outlet side (so it has to be up high close to the outlet return). I got it to work finally, but not as well as my initial test using the canister filter. The mist seems like it might be too fine, (

 

Those are very good points, Tom. I have a canister-type setup and my flow does vary as the floss cloggs. So I'm trying to minimize anything that will affect this any further. I feel that perfect performance from my Mazzei is outweighed by my need to keep things circulating well inside my tank. Great mixing inside the injector does me nothing if I cant circulate it well throughout the tank. If I had a sump setup, and a pump straight from the reservoir to the tank, the flow/pressure in that segment of the plumbing probably wouldn't change that much over time and I wouldn't have to try to compensate for those changing flows/pressures. This is where I would install the injector. I could size a pump to a Mazz. that would give me good mixing inside the injector and have enough flow left over to circulate the tank - and then forget about it - leave it alone.

But, as filter and flow performance decreases over time, it might be useful to have a smaller model Mazzei. There would be enough extra pressure on the injector that the Mazzei performance wouldn't be seriously affected if the filter clogged or flow decreased. There would be enough extra pressure to compensate. If a larger injector only had adequate pressure in the beginning, anything that affected the filter/pump's flow/pressure would have a greater impact on the Mazzei's ability to properly supply co2. I have noticed this. When my filter cloggs, and the flow decreases, co2 injection suffers. The mist isn't very fine, and it takes longer for the drop checker to show a yellow-green. But to me, it doesn't matter that much because I can't go very long without decent flow in my tank anyways. So when I clean my filter, and bring up the flow, the injector performance goes back up also. Both things are addressed at the same time. If I just wanted to let the flow go down over time and not worry about it, I might get an injector that can keep co2 adequate even when that flow decreases.

So it seems that with a smaller model Mazz. you could get more stability in terms of keeping the co2 levels up, but more variability in terms of flow into the tank. A clogged filter would lower the flow even more from the flow already restricted by the smaller Mazzei.

And a larger model Mazzei's co2 injection capability might vary more due to a clogged filter, etc. but would have a more stable flow/pressure over time.

So someone considering a Mazzei injector not only needs to consider their pump's ability, but their type of filter setup, their plumbing, and how their system performance changes over time. Also consider their goals/needs for co2 injection and take into consideration these trade-offs.

Again, thanks for your input Tom. It's always appreciated.

-Mike B-

 

Quote from Plantbrain:
As with the mazzeis, you make as few mistakes, maybe you get lucky the first time, but if you keep going and trying things........eventually you'll mess something up and realize there's more to it.

These exceptions are interesting and seeing why they still work or fail etc.
Then we learn a bit more from them each time.
The method evolves as the hobby has.
Which is to be expected.

This is what I am noticing with my Mazzei setup. I think I have it working like it should, then I learn a little more, or ponder how I can make it better, and fiddle with the injector again. Sometimes I make it worse, but then at least I learn that's what NOT to do. I have tried different gang valves, different plumbing fittings, and now (for Christmas/my birthday) I want a stronger pump. But everyone's help, building off eachother's experiences & ideas, has been invaluable. They have shown me that this system IS intricate, and that there are a lot of factors that play off eachother, and just (for example) the Mazzei is only part of what's going on.

As for cleaning filters, like Tom said, a pressure gage is really helpful. I too think they should be on more filter systems. I love the one I have on my Lifeguard mechanical module. The gage is what I look at to see if anything is going on, or has changed, in my filter/plumbing system. Changes in pressure can indicate that the filter is clogged/needs cleaning, or that there is a leak or airbubble, or that something is affecting the pressure in the filter. Changes in the pressure gage usually translate into changes in my flow of water into the tank. Its great to see how well the system is performing at any one time. I can even see changes in the pressure gage when too much gas being pushed/sucked into the Mazzei injector. If the suction port of the injector is just wide open to the air, the pressure gage rises and flow from the outlets into the tank decreases. Its very interesting to see what can/will affect it.

-Mike B-