well , I think its not easy becauae most researcher used continuous flow reactors and they don't specify either their flow rate or the volume.

so the follow rate will depend on many things°:*-

ozone generator power and output

your water quality ( high organic matter )

also you have be sure that Cl is act as scavenger for OH radical.

so I advice you fisrt to do batch exp. with small ozone genrator output and measure all your water quality and in seawater the effecicny of ozone will be reduced more and you have to make refrence test to see the difference use distteld water with same concentrations of seawater except salinty for sure.

alos you have to be sure that ozone solubilty is depend on Temp and pH and in sea water tempreature around 7.5 and 8 and its not favourite for OH formation.

also the degredation prodcust os ozone treatment will lead to more acidic condiations and this may kill the organisms so monitoring pH is anothe keyword.

kind regards

also becaraful the shape of your reactor can affect the contact rime of ozone on the reactor.

so its not very easy as you thing.

The best way to monitor and control ozone is with the use of an ORP monitor or controller.  ORP stands for Oxidation Reduction Potential, and In terms of your aquarium water, it reads an electrical voltage in Milli Volts (mV) which measures the oxidation ability of the water.  As Ozone is applied the ORP level increases.  Natural sea water has an ORP value of 350-400 mV.  ORP levels of 200 or less in your aquarium are indicative of low oxygen, high dissolved organic, conditions.

Check your bromide, easiest with IC. If it is high bromate may be created, which is carcinogenic compound.

Bromide in natural seawater is always much higher than the concern level for bromate formation known in drinking water. Usually the limit in drinking water is 50-100 µg/L but seawater has 40-80 mg/L of bromide. However, public seawater aquariums doesn't always have so high bromide concentrations if the water is made from added salts such as is the case in the oceanarium in Copenhagen that was made by adding NaCl and CaCl into low salinity brackish water.

Low doses of ozone in seawater oxidises organic matter.

With increasing doses of ozone the ozone residual after organic matter is oxidised will partially oxidise bromide to hypobromite and partially be converted to HO· which mostly react further with HCO3- to form less reactive carbonate radicals. These two processes are undesired as they waste ozone and hypobromite is toxic to the fish. Therefor, as mentioned by Ahmed, is is very important to control ozonation with a redox controller or other sensor to avoid ozonating above the level there organic matter can consume the ozone. 

Ozonation of seawater to produce bromate requires very high doses of ozone at which most of the bromide is first converted to hypobromite. The fish will die instantaneously from hypobromite so cancer is not a problem. If bromate is formed it is actually not cancerous for fish (unlike humans) and bromate is removed by denitrifyers that might be present in the biofilter. 

Article Use of fluorescence spectroscopy to control ozone dosage in ...

I agree with Dr. Mohamed Hassaan, that design of the reactor should be organized well fit with the amount of oxidized seawater related to the time of injection.

Beast wishes.

I agreed with Prof. Hassan and Prof. Anderson.

If anybody still follows this Q we just published another paper on estimating and controlling ozona dosage in fish tanks.

Article Ozonation control and effects of ozone on water quality in r...