Ozone

[Phang]

Hi Guys,

Read with interest regarding the usage of ozone in the mentioned thread....

http://www.sgreefclub.com/forums/index.php...9707ce7f218214d

Anyone out there using ozone currently besides AT.....

Would be good to share your comments and particular set up.......

Maybe also a little explanation on terms like Oxidising potiential...of tank etc...

Thanks..

[Achilles Tang]

Here's all the info you need... got it from another site:

13.1 OZONE:

Ozone is one of the most misunderstood additives used around aquariums. This is mainly because few articles have been written about its function and use, and because even pet stores are not all that familiar with how to incorporate it safely in a salt water or reef system. Ozone is an allotropic and very unstable form of oxygen. Ozone does not exist on its own, it needs to be produced for you to be able to use it, therefore, hobbyists interested in injecting this gas, somehow, into their tank's water need an ozonizer. It cannot be bottled in pressurized canisters.

Because of its strong redox (2076 millivolt), much stronger than oxygen (1360 millivolt) ozone quickly oxidizes a great number of compounds, transforming them into compounds of a different chemical nature, often much less harmful than the original ones. This oxidizing ability is what underlies its use around marine tanks, and its injection into either protein skimmers or ozone pressurized reactors.

Ozone quickly breaks down because it is so unstable. Even in nature it cannot exist for any length of time, unless new quantities are produced continuously. You may have been exposed to ozone without knowing it if you have visited large waterfalls, coniferous forests, or in coastal areas during a massive die-off of seaweed. Ozone is also produced during large electrical storms. None of it can, however, be collected and stored. If you need ozone you will have to produce it right where you need it, and you will have to do so continuously to have an unending supply.

Excess ozone is harmful to all animals in the tank, to humans if too much is present in the air (1/10) mg per m3). Ozone also damages all non-ozone resistant tubing and hose it comes in contact with, and is neutralized in the process. Practically, what this means for the hobbyist, is that unless you use ozone-safe tubing you will lose a lot of the ozone you produce to the chemical reaction taking place with the tubing itself.

13.1.1 WHEN SHOULD YOU USE OZONE?:

If the water quality in your tank is low, which would be demonstrated by low redox potential levels and low dissolved oxygen levels, and a tank that does not really look in good shape, you may wish to consider using ozone to improve your water quality.

Tanks with these characteristics are usually in need of additional equipment to reduce the amount of organic material, alleviate the stress on all the filters because of the high load or poor water quality, and increase dissolved oxygen levels in the process.

Ozone will also keep parasitic disease in check. It may not cure the problem completely on its own, in a short period of time, but it will definitely kill off all free floating parasites that go through the skimmer and/or ozone reactor. Because free floating parasites are the ones that spread the parasites to other hosts, this is a plus.

Ozone also oxidizes nitrites, and can be used to cope with small amounts. Whenever you find nitrite you should, however, look for the real cause and deal with it, rather than using a patch solution such as ozone injection. Typically though, in tanks in which a fair amount of ozone is injected, no nitrites will be present, unless things get really out of hand. In such a case, major changes may have to be made to your system to bring it back in line.

13.1.2 HOW IS OZONE PRODUCED?:

Ozone is first produced by an ozonizer, or ozonator as it is sometimes called, and then mixed with water either in a protein skimmer, foam fractionator, or it is injected into an ozone reactor.

Two types of processes are used to produce ozone. Corona discharge units use very high voltage transformers (several thousands of volts) and transform some of the oxygen that is blown through a special tube inside the unit, into ozone. To do so efficaciously a good air pump is required. Wisa 200 and Wisa 300 pumps are, in my opinion the best suited for this process. Typically 1 percent of the oxygen passing through the tube will be converted to ozone, at 6000 volts.

Many factors affect the process, and generating ozone is not at all as simple as it sounds. Ozone generators can be very temperamental indeed. Moisture and dust in the air reduce the output of these type of units considerably. A loss of 50% or more is not unusual, especially since air around aquariums is usually extremely moist, over 90% is not uncommon. Dust inhibits the formation of ozone as well, which is the reason some hobbyists buy and install small in-line air filters.

A second process used, is to blow air over and by a specially constructed bulb that emits light in a specific nanometer range, and generates ozone while irradiating oxygen that passes through the unit as part of the air that is blown into it. These units too are rather touchy, as moisture, dust and temperature all affect the amount of ozone that will be generated, although to a lesser degree than in Corona discharge units. These units operate at regular house current voltages.

In both of these processes you must blow air through the unit itself, except if you have installed a venturi protein skimmer as the latter such in their own air, and do so through the ozonizer if you have installed one. In this respect, venturi skimmers can save you a good deal of money, as a strong air pump can cost quite a bit of money.

Several companies now offer a number of models to fit just about any situation you may be in. Small units from Sander producing 25 or 50 mg of ozone are available, and so are much larger units producing 250 mg, 500 mg, or even 1.0 gram from TAT. Regardless of which unit you buy, look for a long warranty because you may need it. Ozonizers can be very temperamental.

As indicated, moisture greatly reduces the amount of ozone your unit will produce. Adding an air dryer to your system is one solution, as it will pull moisture out the air that goes through before it enters your ozonizer. Problem is, air dryers need constant attention. The compound that absorbs the moisture needs to be dried itself just about every couple of days (and I do mean 2).

This is laborious, not as easy to do as you think, and many hobbyists quickly tire of it, and neglect the dryer. As a result, less ozone than is necessary is injected into their system.

The alternative is really simple. Buy a unit that produces about twice the amount you need, and do not use an air dryer. You will still end up with enough ozone and will not have to mess around with air dryers and the compounds in it, often calcium sulfate or silica gel.

Which unit is right for you depends on many factors. Mostly on the size of your tank, and the load you keep in it. Additionally the type of unit you need is determined also by whether or not you will be using an air dryer and an in-line air filter.

13.1.3 INJECTING OZONE:

Not much time needs to be spent on this as most hobbyists know that this can be done in two ways: through a protein skimmer, or with a pressurized ozone reactor.

After ozone is generated the mixture coming out of your ozonizer contains both air and ozone. This mixture is pushed into the protein skimmer and escapes into the water from so-called air stones. Since protein skimming happens more efficiently when the bubbles are small, appropriate air stones should be used, and they should be changed as soon as the size of the bubbles starts to increase. You may want to make it part of your maintenance schedule to change your air stones once a month. Limewood and oak seem to work best. The latter requires a stronger air pump than the former, because they offer more resistance to the air, however they make much smaller bubbles.

Some hobbyists want to use two small units rather than one, usually because they already have them. The correct way to hook them up is in parallel, not in series. The above diagram shows the correct method of hooking up 2 ozonizers.

When ozone is injected into a reactor, often just a plain acrylic cylinder filled with a medium to disperse the water, the process can be made efficient by raising the internal pressure of the cylinder. As the partial pressure of ozone is increased, it is forced more strongly into the water and a higher efficiency rate is achieved. What this means in simple terms, is that you get more oxidation from the amount of ozone used.

You will remember that earlier in the book my premise was that it does not really matter how much ozone you use, as long as none can be found in the water in the tank itself. This must, of course, be somewhat qualified! My recommendation is that you size the ozonizer you acquire to deliver 2 mg per gallon water in your system, and that you do not use it with an air dyer, and preferably install a redox potential controller.

Two milligrams per gallon in your system, rounded off to the nearest available size of ozonizer available, may seem high. It is not in my many years of experience with ozonizers. I personally use a 500 mg unit on a 135 gallon tank, but because of all the water in the sump and pipes, the true volume is really around 200 gallons. Even with that 500 mg unit I do not find any residual ozone in my system, other than in the water coming out of the skimmer.

Because no residual ozone may be present in the water that is in the tank - such could be very damaging to your corals - all the water coming out of the skimmer must be flowed over activated carbon before it remixes with the main water mass. Do not take this requirement lightly, especially if you follow my recommendation with regard to the amount of ozone used. As the activated carbon neutralizes the ozone, it exhausts its ability to do so. Change the carbon regularly. Once a month is a safe frequency.

13.1.4 USING REDOX CONTROLLERS:

As you "clean up" the water in your tank with ozone, and reduce the amount of pollution, especially organic pollution, the redox potential will go up. If you now adhere to sound feeding and stocking practices, it will take less ozone to maintain the water at that quality level, than it took to get it there in the first place.

This may seem like a dilemma. It is really not. If you operate a redox controller on your tank, the unit will shut your ozonizer on and off whenever the redox goes over or below the set point. Because of this automation no changes have to be made to your system, and you can let the ozonizer operate exactly the way it has done before.

If you do not use a redox potential controller you must use a different method, but you must use a redox potential meter, a device that will cost you between $50.00 and $100.00 depending on its quality. Buy one, or borrow one, or rent one from a pet store. You can rent such units from TAT as well. A one week rental will cost you $20.00, plus a refundable deposit of $30.00. The rental can even be applied towards the purchase price (price applied at the time of this writing, check with them for current pricing).

Proceed as follows, do not switch the ozonizer off:

Obtain a redox potential meter.

Measure the redox potential in the morning and make a note.

Measure the redox potential in the evening twice, once before the lights go out, and once after they have been out for about 2 hours. Make notes.

If the three readings you obtained are well below the values suggested in this book, your water quality is not nearly where it should be and you should leave the ozonizer on all the time. First clean up the water conditions and start the procedure again when the redox is over 350 mv. If it is, proceed with then next steps.

Measure again the following morning and again twice that evening.

Do so again on the third day.

You now have three days of morning and evening values, and you will have a fairly good idea of how your system evolves redox potential wise.

On the fourth day take only a morning reading, and write it down.

In the evening take your first reading. Write it down, switch your ozonizer off for 15 minutes and then on for 15 minutes and off again for 15, and on again for 15. Use an inexpensive digital timer with 1 minute on and off cycling time to do so. You can buy these timers at Radio Shack.

After about 3 such cycles, take a reading of what your redox is when the meter is on, and a little later after it has gone off but is about to come back on. This will give you a high number and a low number. Measure again just before the ozonizer goes off again. This will give you another high reading.

If the high reading you obtained after the cycling is just about the same as the one you had when the ozonizer was running continuously, a 15 minute cycling time will be all right for your system to stay around the same redox potential.

If it is not, reduce the cycling to 10 minutes and conduct the same tests.

Do so until you have found the correct switching time for your system.

Although this exercise may be somewhat time consuming, and although you may have to repeat it several times, it certainly is less expensive than acquiring a redox potential controller of good quality.

Not only will it allow you to operate your ozonizer more efficiently, but it will, in addition, give you a better understanding of what is going on with your tank, which in itself is a plus.

13.1.5 CONCLUSION:

Whether you like it or not, the use of ozone will greatly improve the quality of the water in your system. Used as explained in this chapter, ozone's mystique is no longer a problem, and it can safely be used, even by a novice.

Used in the amounts suggested it will bring the quality of your water up to levels where it has not been before. Both the animals and the appearance of your tank will reflect it and the overall result will be a much more vibrant looking aquarium.

Read up on ozone in other books if you still feel uncomfortable with it. Talk to others who have used it for a long a time, or call us at Aardvark Press. We will gladly help you.

13.2 PROTEIN SKIMMERS:

13.2.1 INTRODUCTION:

Whether you use a protein skimmer of the columnar or of the venturi type, and whether you use it with or without ozone, is a matter of how much you want to improve your water quality. My experience has taught me that you must use one, if you want to improve that water quality. There is no way around it, except running a largely understocked tank with an oversized filter.

Although the use of protein skimming has greatly increased in the last year or two, many hobbyists still feel that such filtration may not really be required, or that they can get away with a real small unit. Such is not my experience, and such is also not the experience of recognized German authors such as G. Hueckstedt, P. Wilkens, Sander and Lemkemeyer.

Protein skimmers work on the principle that if small air bubbles are chased forcefully through a column of water, they will pick up organic and other material as they rise, and create a strong foam that contains all the matter they have picked up. Removing that foam removes the matter, and since it is no longer part of the system, it cannot break down and stress the filtration and the animals in the tank. Just looking at what comes out of a well operated skimmer should convince even the skeptics.

13.2.2 TYPES OF SKIMMERS:

Two types are commonly available in the hobby: columnar skimmers and venturi skimmers (also called power skimmers). Columnar skimmers are more widespread and therefore more familiar. They are less expensive to make, especially when certain of the parts are molded, as is the case in some of Route 4 Marine Technology's units, and of the of Sander ones.

Foam fractionation, as it is called in an industry where such filters emanated from, has been around for decades and is nothing new or fancy, just an efficient way to remove certain compounds from water.

The problem the hobbyist must deal with when deciding on the purchase of a skimmer is not only which type (columnar or venturi), but the size and the quality of the unit. This is especially so if ozone is to be used.

The photograph shows both a columnar and a venturi skimmer. It should be obvious that venturi skimmers are much smaller and can, therefore, be placed underneath the aquarium, in the cabinet.

Venturi skimmers operate on exactly the same principle as columnar ones, but differ in the manner in which the air is mixed with the water. Rather than using a rather crude wooden air diffuser approach, specially made valves, manufactured manually or molded, are used to generate extremely small bubbles very forcefully, much more forcefully, and in larger quantities than is possible with air stones. Because of this improvement in bubble size, bubble quantity and mixing, the units can be much smaller. And since space underneath a tank is always at a premium...

Being able to hide the skimmer from view is one advantage of venturi skimmers, but the additional efficiency is much more appealing. Better efficiency means better water quality, means a better looking aquarium. TAT builds venturi skimmers into all their trickle filters, making that filter perhaps the best buy on the market, because you get not only one of the best filters, but for the same price you get a venturi skimmer as well. And since stand alone venturi skimmers can cost $500, you may want to think about this carefully if you are in the market for a filter.

Whereas columnar skimmers require a fair amount of adjustment, venturi skimmers usually do not. You set them up and regulate the water flow and the foam height, and you are skimming without having to readjust the levels ever so often. This, too, is an advantage to consider and factor into your decision.

Venturi skimmers with molded venturi valves are more efficient than venturi skimmers with manually made venturis, but your system may not need the higher efficiency of the molded venturi if it is only stocked at medium level and operated with a good trickle filter. Talk to the manufacturer and then decide which one is better for you. The difference in price is worth the time.

With any skimmer, but especially with venturi skimmers, make sure that you can operate them with a great deal of ozone if that is what you have in mind for your system. Not all can.

13.2.3 OPERATING THE SKIMMER:

After installing your unit, operate it with a pump, or a by-pass from the main water return line, and adjust the flow rate to equal about 1 to 1.5 times the amount of water in your system. If you do not have a flow meter you will have to gauge this somewhat. The amount of water you push through the skimmer is not extremely critical, but enough must go through for all the water to be skimmed in a regular fashion. Many hobbyists flow greater amounts of water through their skimmers and report better results. Experiment a little until you have it set right.

In fact, if you own a redox potential controller or meter you can measure the redox of the outflowing water at various speeds and decide on which one is best. That would obviously be the setting you would want to select.

Venturi skimmers typically require more water flow because of the venturi valve. The more forcefully you push water through the valve assembly, the more forcefully you will draw in air, and the better skimming levels you will attain. On the venturi skimmer in the photograph 600 gallons per hour is a minimum, but what an effect.

Because ozone changes the consistency of the foam that develops at the top of the skimmer, levels and foam must be adjusted each time you make a change in the amount of ozone that is injected. This applies to all skimmers. Observe the levels when you make the change and readjust if necessary. Sometimes changes in water and foam levels take time to become apparent. Do not walk away from a skimmer unless you are sure that the level is not changing. This may take 10 to 15 minutes to be visible.

Air stones wear out quickly, especially if used with a lot of ozone, and the bubbles they produce will rapidly increase in size. This reduces the efficiency of the skimming process a great deal. Your air stone(s) need to be replaced when this happens. Make it a point to do so. There is no sense spending money on a skimmer and then not operating it the way it should be operated.

If ozone is injected into the skimmer, use ozone resistant tubing to connect the output of the ozonizer to the air/ozone mix input on the skimmer. Not doing so reduces the amount of ozone that is actually available for the skimming process. Norprene* is the recommended tubing. Silicone tubing will last for a while, and polysulfone is the best but also the most expensive, fetching as much as $8.00 a foot retail for the very high grade quality.

If ozone can be smelled in the room where the skimmer is placed, suspect that it is coming out of the top of your columnar skimmer, or that you have a leak in the ozone line. The former is more often than not the explanation though. To prevent this from continuing, install an ozone cap on the top of your skimmer. This is a round cup, of the same diameter as the top of the skimmer, with a perforated bottom, and filled with activated carbon. All air/ozone coming out of the skimming column must now go through the carbon before it can escape into the free air. Since carbon neutralizes ozone your problem should be solved.

Clean the top cup of your skimmer regularly. This will allow you to better determine where the foam level is and it will also reduce odors that may otherwise emanate from the scum that collects in the cup. Alternatively, make a connection with a small diameter hose from the skimmer cup, to a larger container with a lid, placed on the floor. Scum will now flow from the top to that container, and the lid will prevent odors from getting into the surrounding air. You will have to make a small hole through the lid to pass the hose through. Make it tight. Some companies, for example, Route 4 Marine Technology and Marine Technical Concepts, offer special containers to do just that.

Certain additives can make your skimmer foam much more forcefully than normal, usually because they contain binders or colloids, or both. To prevent the skimmer from overflowing, test a small amount of any new additive you plan to use and make sure it does not affect the way your skimmer operates. Be especially careful of KH generating compounds, some vitamins, some nutrient elements, and a number of others. This does not mean that you cannot use them, but you must add them only in very small quantities. In the case of KH generators this is not practical, and I suggest you get yourself one that does not affect your skimmer.

Skimmers are meant to run 24 hours a day. I see no reason why you shouldn't. When a time comes that little is to be removed from the water, the skimmer will not produce as much foam. That's all. When later on, e.g. after feeding, or when algae die, and they do all the time, more organic matter will be present in the water, and the skimmer will start removing it again. Do not be misled, a skimmer that has been running for a while may not have anything to remove from the water, so it won't. Such does not mean that your skimmer is not working properly. It probably is.

Once you have adjusted your protein skimmer properly, leave it alone. The more you adjust, the more readjusting you will have to do, and the more unnecessary work you are creating for yourself. Note that this applies to both columnar and venturi skimmers.

_Small Reef Aquarium Basics_, and a few issues of _Marine Reef_, the newsletter we publish go into even more detail on skimmers and outlines a chart on how to size your protein skimmer accurately. You may wish to refer to them if you need still more information.

Two volumes of back issues of _Marine Reef_ now exist. Volume one, Year one includes issues 1 through 17, and Volume two, Year two includes all issues from 18 through 34. Both are available form Aardvark Press for $30.00 each, or for $50.00 if you order both of them. To keep yourself up-to-date on what is happening in the hobby, and to learn more about the requirements of the animals you keep, consider subscribing to the newsletter. It will be a worthwhile investment.

[Phang]

Where can I get this ozoniser and how much would it cost??

[Stenopus Hispidus]

AT, Great job in compiling that passage. Very thorough and answers most questions.

Can't believe they have rental arrangements for ORP monitors? But must admit its quite a cut throat price to buy the monitor here and the price do not even include a controller...just plain monitor. Oh well...

Phang, Maybe you can check with Sam. I bought my Coralife from him last time. Can't really recall the price now. Think its in the region of $200-$300. Dunno whether he has ex-stock cos he doesn't hold Coralife brand anymore. Maybe he has a Kent Marine version but then again Kent Marine may not have an ozoniser.

I am curious about AT's very own Sanders. I don't see it around and may wanna try that brand. Waiting for him to post a pic when he gets his d.cam back.

[Hon]

I did own a 50mg Sanders ozoniser many year back. I got it from Petmart for around $220 I think. Sanders ozoniser is easily available in Singapore. Other brand I not so sure.

AT,

Can you talk about your DIY air dryer? How to deploy it?