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:

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-

Getting good flow bubble rates with mazzeis can be a challenge due to the fact they actively suck gas into them, vs backpressure from disc, which have their own trade offs(reduced flows and CO2 rates after they slowly clog and as the plants fill in.........)

Not taking into account things like plant growth/biomass changes through time, disc clogging, even if the pH claims the same, the system can really be really changed and you will never see it.

I think if the rate of CO2 is even relatively the same, the limitation is something else.
After any big trim etc, do a large water change.
You'll save shrimp and other fish etc, and cause them less stress and also have less algae chance/potential.

Then you can re set the system with nutrients.
Light, CO2 and nutrients, resetting these will help in virtually every case unless it is something weird with the tap water.

Regards,
Tom Barr

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-

You sound like you have it figured out pretty much.
Good deduction.

If the tank is rather large and you want the glass disc out of there or hate cleaning them, then the venturis are still able to beat the disc. For smaller tanks, Glass disc are still pretty decent.

The mixing value for the venturis is ideal for massive tanks, as they mix and add high flows to the glass/water mix, whereas the disc do not, only the water that flows by them and where that water goes afterwards..........small tanks do not have much mixing issues, larger tanks do.


Regards,

Tom Barr

Face planted IME with my 384 ½ Mazzei in a 90gal, there is absolutely no comparison between the two. The Mazzei's ph pulldown ability cannot be matched by a glass diffuser at ....least in my experience.

The difference between our setup is I am using a 384P w/ 1100gph@ 28ft head so I am able to provide more pressure flow which in turn mixes, disentegrates and dissolve co2 more efficiently.

Just wanted to clarify to the masses that a glass diffuser and Mazzei is not the same animal when Mazzei and pump is correctly matched

Hahaha, 1100gph is more than enough responsiveness on a 90 gallon!

Yes, in that case, no comparison..........no way to mix that much gas into water without something like the the venturi.........

I have a lot of flow in my tanks, so I know that this lack of flow is a non issue.
I also want to throttle the flows back some, so this gives a nice trade off.

I use slow flows on the over flow system and high flows on the closed loop canister.
I use two systems on most tanks so I can do a number of things and balance each's trade off.

Good point of clarification mrkookm.

Going back to the idea of trade offs and two independent systems, my client's tank has both, and we/you/myself can also do the same here.

Have a pair of disc or a single in the tank and venturi and then you can see on the same the tank.

But as mentioned, sizing the venturi and pump to match is a good idea and critical. I sort of eluded to that in a round about way


Regards,
Tom Barr

Mike-B,

Thanks so much for taking the time to explain this in such detail. A great job!

All,

So, I have a 180 gal with a 500gph pump running an AM1000 with venturi mod with outlet of c02 reactor near intake of main tank pump......

I use an 1800 gph pump for the main pump in my sump.

I have the main pump also split to dual outlets back to tank. Assuming I setup similar to you with the mazzei just PRIOR to the T splitter....

Questions:

1. What size mazzei do you suggest for my 180 gal tank? Please PM with links thanks

2. Is my 1800 gph sufficient to run it as I want? Or do I need a even bigger pump? Especially in light of mrkookm's comments.

3. Can I continue to run my current reactor setup, or is the idea to REPLACE the reactor with the mazzei?

I thought that keeping the two systems would cause c02 enriched water through the mazzei and that it would be better combined.

Tom, is this what you meant by



I assume that this would entail splitting the c02 input to run both ways, correct?

Is this the better option? Or should I run both but separate somehow? You refererred earlier to two independent systems.

Thanks again for your help.

For a 180gallon I would suggest the use of a 384P injector which can be found at Ryan Hero


The more pressures put to the inlet of the Mazzei is what you are after so therefore a pumps 'head' is really important, not the flow really. What is the spec of your pump? Is it a submersible pump?


The Mazzei is meant to replace the reactor.