Best Ozone Delivery Method

Superpuma

New member
Hi

The title says it all.

Have used an ozone reator, found it struggled to maintain 400orp, the amount of carbon used in the carbon reactor post ozone reactor caused HLLE issues for my yellow tangs.

Skimmer delivery, this is better... But with 50mg of ozone being delivered is more or less water/air better in the skimmer? By this l mean a 1000 or 2000 lph pump, a bigger or smaller skimmer. If smaller then surely a reliable little skimmer purely for ozone delivery is the way to go, leave the main skimmer to do it's thing and those that use ozone have a dedicated skimmer for it...... Any experiences?

Mike
 

wolfblue

New member
it struggled to maintain 400orp,

That's all you would want anyway. If it struggles to hit 400 then there is not much chance it can go very far past 400. And that's good because 400 is actually starting to be borderline bad anyway. If that's a accurate number then your getting close to bromine territory.

What is the volume of the skimmer your using as a contact?
What is total system volume?
What is the location of the probe?
 

Superpuma

New member
400 is all l want to achieve, l'd like to achieve it and have it stay there, all being monitored by an orp controller of course.

System is 500 litres ( 125 gallons ), probe is in return section of sump, probe reads the same where ever l put it, probe is calibrated. By volume of the skimmer do you mean the physical body of the skimmer or the volume of water it handles? Skimmer has a 2000 l/h pump, volume of the body is around 3 litres l suppose, it's an average Bubble Magus 180cs. l'm thinking on getting a smaller skimmer for dedicated ozone use, 1000 l/h, longer contact time.....

Thanks for your reply.
 

wolfblue

New member
ORP can stay at a narrow value range or it can vary during the (24h) day. Typically it starts to rise after dark, hits a high early in the morning and falls all day. Its fine if you swing from say 350-400 on a daily basis. If you wanted to hold it near 400 all day you might need a sophisticated proportional integral derivative (PID) ORP controller that changes how much ozone is produced. So the ozone generator is making more ozone when the ORP would be 350, and less ozone when the ORP would normally be 400.

"ORP measured on a natural coral reef ranges from 350 "“ 400 mV" (Moe, 1989).

But... exact ORP values in the home aquarium environment can mean next to nothing. The probes are often said to read 20 either way but its often much worse than that. A prominent water quality guy once said "give me a bucket of water and three ORP probes and I will show you three very different ORP values". Water can be very healthy and crystal clear at 270 and even at 230 for some systems.

And then there is residual oxidants. I usually just say bromine because people can relate that to a hot tub or swimming pool. When ozone is applied to salt water a whole bunch of bro stuff is created. Like bromide, bromite, hypobromite. Does this stuff sound good for a reef tank? Probably a little better than chlorine but not much. People often use ozone because they think its a oxidizer and it is. Some ozone will directly oxidize some stuff. But ozone is quickly being converted into other oxidants. The secondary oxidants probably do most of the oxidizing work. And some of the secondary oxidants can last a long time. So we run the effluent through activated carbon.

What you want is there to be about the same amount of stuff that can be oxidized, as the available oxidants. So the carbon is not taking a huge load. But often people in here are making way to much ozone. A big proportion of the ozone is doing nothing except burning up the carbon. And you have increased risk of oxidants reaching animals.

Another problem that could come from ozone use is that ozone oxidizes nitrite into nitrate. So you could starve out the bacteria that does that very same thing. Then the ozone generator breaks. It may quit working and you think its still making ozone. And you get a nitrite spike. So I recommend routine nitrite testing for people using ozone.

But I am running low on time. I will add later why I think 50mg is a awful lot of ozone for 125 gallons. And I want to talk about flow rates and contact time. And why I think 350-370 is a better cutoff. Maybe 8 hours from now.
 

Superpuma

New member
Thanks John, a very informative reply. You're correct when you say orp levels rise during darkness and hit a peak in the morning. I am actually lucky if l get as high as 400, first thing in the morning it's around 380, it'll drop to 330 during the day, as darkness falls it creeps back up again.

I add ozone as a precaution against parasites, l've been hit by various before, even with qt, l do my utmost not to see beautiful fish die a pointless death.

It will be interesting to hear what you have to say about flow rates.

Thanks Again

Mike
 

zoomonster

New member
I considered the reactors when I built my latest tank but went with tried and true method of ozone being sucked (well small airpump/dryer on ozone) into the venturi of my SRO XP3000i. I do let the output of the skimmer run over a carbon bag. I run my Ozotech Poseidon 200 at about 40% and controlled by ORP probe on Apex have no issues keeping ORP in the 365-375 operating range. Well I do have an issue of the ORP probe fouling about once a week and readings go high i.e. it might read 400+ but after vinegar cleaning it drops off to 300 or less. Just me but for saltwater 350-375 is more or less the norm for ORP. It might be that if you have a 50mg unit it's insufficient or in need of cleaning or air drier service to operate at peak (if it ever really did produce 50mg new).
 

Superpuma

New member
I am actually starting to have doubts about my ozonizer, the smell of ozone is there, but not like it used to be.... I've cleaned the ceramic disc on my unit but it does have some deep down staining, it may well be affecting production. I've sourced another unit, the plot thickens.......
 

wolfblue

New member
it does have some deep down staining

Brown or blackish? Are you running an air dryer? With no air dryer moisture reduces output and creates nitric acid. Brown stuff that destroys metals and some plastics inside the generator.

Also 330-380 is what I would call the perfect range for salt water. FWIW ozone use in aquaria is not a hobby for me. I'm using 200 grams an hour (not mg), I decide all on over 300k gallons of water here and ozone is one of my areas of expertise. I'm not a expert and I never even played one on TV. But I have real ozone experts numbers in my phone. 400 is the hairy edge in salt water. But there is more to it than just a number. zoomonster has got the "feel" for a better number. He knows what 405 really means on his system. Doesn't really mean 405. More in 2-3 hours...
 

Superpuma

New member
Am l using a dryer? I'm assured by the manufacturer of my " cold plate discharge " ozonizer that an air dryer is not reqd, l've tried it with an air dryer, it's better without it.

I've discovered where the stain came from on the disc, the inlet nozzle on the ozonizer was so hot that it partially melted and began to suck in molten inlet tubing. Tubing is brown, tube is positioned external of cabinet, it sucks in dry air.

But my real question is..... In a system of 500 litres would ozone be best delivered to a skimmer with a 2000 or 1000 l/h pump on it?

Thank You very much for your knowledge and input.
 

wolfblue

New member
First of all, I think the best place for ozone is in the protein skimmer. Not because its convenient, everybody already has one. That is true and it does help. But more because I think it aids in skimming. But it gets complicated because a small amount of ozone helps some things skim better, and makes some things skim worse. The net overall effect is better skimming because of a micro flocculation type effect, if you don't over do it. Too much ozone tends to make more and more things skim less effectively as the ozone breaks the carbon bonds of things that would have skimmed out. Too much ozone and that stuff goes back in the water when it could have been removed. At a low dose like this you still get the crystal clear water that most want from ozone.

So the question comes to mind of how much ozone aids in skimming and where does it really start to go the other way. Testing (by people that I can not identify without their permission) has shown that effective amounts of ozone in the protein skimmer come in at only 0.01-0.03 mg/l. As you move to more than that you start to have a situation where skimming acts like it would without ozone, but you still have sterilization from the ozone. Then with even more ozone you have more sterilization but the ozone starts to impede the action of the protein skimmer. Where this is region is I really don't know. RK2 sizes ozone generators for 0.1 mg/l at two minutes dwell, and I set them at 20-35% if I have no reason for something different.

Just as a ballpark type thing lets say I have 1 mg of ozone. So that would be good for 33-100 liters of water if my aim is to aid in skimming. Now lets say I have 50 mg's of ozone over 1 hour. So that's good for 1650-5000 liters of water. I have a 2000 l/h pump and that falls in the flocculation dose range, but my skimmer volume is only 3 liters. There are 3600 seconds in an hour so I am pumping a liter in 1.8 seconds. So my ozone averages about 6 seconds or less before it hits the carbon. And the pro's are doing 90-120 seconds of contact. But they tend to have more in the way of load than a reef tank would have.

So, If your getting good action from the protein skimmer like it is I think you leave it alone. 330-380 is perfect. I think you just repair damage to the gen and run it like you have been. Don't buy a bigger gen for a 125 gallon. You don't need to hit 400, set the controller to turn it off at 400. Keep a generous amount of carbon where ALL the water goes through it before reaching any animals. Test for nitrite at the big weekend maintenance or anytime you have a doubt. And know you wont kill ich unless you have real slow flow and real long contact times. You would need to rig up a coil contactor to kill ich.
 

wolfblue

New member
Oh and then I went back up top and saw HLLE again. Forgot about that. The thing is you must use carbon after the ozone. Using ozone with no carbon gets tricky and expensive. I have seen HLLE where carbon was never used but I cant get into the causes. You might be better off with a slow flow UV. If you go slow enough you can kill the bugs and clear the water up also.
 

Superpuma

New member
Very glad l started this thread and you responded. My plan......

You mentioned a slow flow uv, l have that set up too. I'm going to buy a small skimmer, this skimmer l'll use purely as an ozone reactor, it'll be something like a Bubble Magus C3.5, then the main skimmer can do it's job as a skimmer, l'd sooner sacrifice a smaller/ cheaper skimmer than a BK or MTC that l plan to use on this system. As said previously, l reckon l've damaged the disc on this ozonizer, it isn't performing as it was, orp 363 this morning, was as low as 325 early evening yesterday. In a few weeks the replacement ozonizer ( same model, 2nd hand ) will be here, it'll be interesting to compare.

Thanks

Mike
 
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