UV Sterliser

[axelfaz]

HI al just wondering what watt UV Sterliser i should use on a 200l tank filter will be 1000lph :? :? . thank you


Cameron

[oscar]

Axelfaz,

If you go back through this section you'll find a heap of posts about pretty much the same question. In fact one of them was me asking. I have a 200L and a 240L tanks that i was fitting them to.

There are two options, an internal or an in-line system. The hands-down winner i got as a response was to use the AA UV Sterilisers available from Age of Aquariums.
The benefits of these units are many (including):
Bang for buck is brilliant at $120 (24W) each.
Flow rate from the powerhead is matched to the bulb so you are getting good sterilisation of the water.
Replaceent bulbs are cheap as.

The only drawbacks are:
More gear in the tank.
The inlet sponge needs to be cleaned regulary to keep the unit performing optimally.

As a result of the responses i purchased 2 of the 24W internal units. They do the job quite nicely.

[axelfaz]

hi all just a silly question ive finally set up my uv do you guys leave it on all time :oops:


thanks cameron

[Benny]

yep, except when medicating

Benny

[DR.V]

yeah , i leave them on 24/7 too

[endless]

are the external ones ok to keep on 24 hrs a day? if i remember correctly i think the instruction says dont leave unit on for more than 3 days consecutively.

[oscar]

I have 2x24W internals on two tanks and only turn them off when medicating.

Not sure about the external jobs.

[dreamer]

i keep mine on 24/7 just because im too lazy to turn it on/off

im using coralife turbotwist 9w on my 120g tank but i dont see a real different with water clarity maybe i should have gone with 18w...

[axelfaz]

hi all how long does the globe last for being on 24/7 :shock:
also thanks for the replys

Cameron

[Ben]

Hi Cam,
hows things mate!!

it is recommended that the globes be replaced every 12 months. But in my opinion it would not hurt to replace them every 9 months, as after a while they loose there affectiveness.

HTH

ben

[axelfaz]

hi Ben
all is well mate thanks for the reply. new equipment always throwes me for a six I lost over 50l of tank water just hooking it up long story and very wet carpet. :roll: :roll: :roll: :shock: . six ring leopard from Merrilyn are going into the tank tomorrow. So just making sure all bases are covered.


Cameron

[DR.V]

are the external ones ok to keep on 24 hrs a day? if i remember correctly i think the instruction says dont leave unit on for more than 3 days consecutively.

Yep, mine is external ones, and I keep it 24 hours.

If you like you can use a timer to switch if off at certain time.

HTH

[endless]

yeah im using a timer at the moment 15hrs on, 9 hrs off

[Proteus]

yeah im using a timer at the moment 15hrs on, 9 hrs off

Sorry, but that is the worst thing you can do, and i dont say that lightly.

You must think of your UV Sterilizer the same way as you do for your filtration, it needs to be on 24/7, no ifs, buts or maybes.

By turning it on and off, you are creating a very unstable environment, plus decreasing the lifespan of the tube by up to 50%.

[Proteus]

How a UV sterilizer Works
A properly-sized UV sterilizer sterilizer can rid your aquarium of free-floating algae, harmful bacteria, or certain parasites depending on the wattage and the flow rate through the unit. As a result, UV sterilizers minimize disease and keep your aquarium cleaner, clearer, and healthier.
The UV sterilzer should only be turned off when using medications, especially chelated copper treatments, as well as during maintenence where there is no water flow through the quartz chamber.

Choosing a UV - Factors to Consider
Before selecting a UV sterilizer, determine your primary objective – whether to help control free-floating algae or to control parasites. By doing so, you will be able to select the proper unit to achieve your intended goal.

UV sterilizers work on the principle that special fluorescent UV lamps, at a peak wavelength of approximately 254 nanometers, can effectively irradiate microorganisms in aquarium water when exposed to this light. UV light in this wavelength alters the genetic material in the organism’s nucleus, shortening its normal life cycle. However, the application and the efficiency of a unit are determined by flow rate as well as the wattage and age of the bulb.

[endless]

Thanks for the info proteus. ill ditch the timer

[wyldchyld01]

probably a dumb question here, but proteus do you know if it is only because of the quartz? copper doesn't react well. oxidation i've been told happens and hence possible weakness of uv lamp. have i been told a furfy??

i was looking at these internals Ben reviewed, doesn't seem to have quartz difraction.

Brenton

please tell me i'm wrong by all means

[Benny]

HSC chemistr
Oxidation is LOSS of electrons....

theres no solid copper, going thru oxidation and ionizing into a copper salt...

Someone plz correct me if im wrong, i was goin by "OILRIG"
Oxidation
Is
Loss (of electrons)
Reduction
Is
Gain (of electrons)

therefore the chem eqn to me would be
Cu(s) --> Cu2+ + 2e-

where...

Cu(s) is Copper in a solid state
Cu2+ is A copper ion sharing two electrons with other things
2e- is two electrons each with a -1 valency...

Sounds like a bit of a lie to me..!

Also quartz is totally inert being a silicon based compound and wouldnt affect the chemistry...

Go figure mate,
I cant understand where oxidation is...

UV sterilisation was what i thought to be a physical process, nothing chemical about it...

Benny the chem geek (or wanna be chem geek) signing out
(im an accountant, dont blame me if im wrong with this!)

[Merrilyn]

Benny, Chem geek or not, it sounds reasonable to me, and confirms what I've read.

Thanks for the information. :P

[Proteus]

UV light turns copper based medications inert.

i.e. it is rendered ineffective.

All UV tube manufacturers recommend turning off your UV system when treating with various medications.

geek or no geek talk, that is the way it works.

remember, UV light is radioactive, there is more to it than a simple chemical equation.

[Benny]

since when is UV radioactive????

do you understand redox reactions???

i was disproving that oxidation occurs...

It would be more likely to cause reduction in any case... i know it stops meds working... I was just saying that its not oxidation......


Find for me please somethin that explains your UV is radioactive theorey?

[Proteus]

Read the label on all UV tubes

[Proteus]

TUV disinfection lamps are
low-pressure mercury-vapour
discharge lamps consisting of a
tubular glass envelope, emitting
short-wave ultraviolet radiation
with a radiation peak at 253.7 nm
(UV-C) for germicidal action.
The glass filters out the 185 nm
ozone-forming line.A protective
coating on the inside limits the
depreciation of the useful UV-C
radiation output (Longlife lamps).
PL-S have a specially adapted
starter providing almost instant
starting characteristics already
built into the lamp base.

Note

The UV-C radiation output of
these lamps is indicated by the
following warning sign.

(image below)

Radiation of these lamps is
harmful to eyes and skin.
Installations with these lamps are
to be screened off completely.

Benny, I suggest when you have kept fish and used this equipment for a few years, then offer an opinion, however using text book knowledge simply doesnt cut it.

Given that some if not all UV tubes are alleged to have Krypton-85 gas in them, that is where the issue lies.

More detailed info can be found HERE (http://en.wikipedia.org/wiki/Ultraviolet)

[Proteus]

This should explain things a little better.


Krypton

Uses: Krypton has some use in the lighting and electronic industry. A radioactive isotope of krypton, Kr85, is widely used in the medical field in heart shunt studies, and as a triggering agent in discharge type electronic tubes.
General

Krypton is named from the Greek word kryptos, "hidden." Traces of krypton are present in minerals and meteorites, but the usual commercial source is the atmosphere, which contains 1.14 parts per 106 by volume. Krypton also is formed by the nuclear fission of uranium triggered by slow neutrons: this source may be expected to become increasingly important because of the growing number of fission-power plants. Krypton has isotopes of every mass number from 74 through 95; six, with mass numbers 78, 80, 82, 83, 84, and 86, are stable. After it has been stored a few days, krypton obtained by nuclear fission contains only one radioactive isotope, krypton-85, which has a half-life of about 10 years, because all the other radioactive isotopes have half-lives of three hours or less. (The half-life is the length of time during which one-half of
any original amount of an unstable substance decays.)

Because its boiling point is about 30 C higher than those of the major constituents of air, krypton is readily separated from liquid air by fractional distillation; it accumulates along with xenon in the least volatile portion. These two gases are further purified by adsorption onto silica gel, redistillation, and passage over hot titanium metal, which removes all impurities except other noble gases.

(Kr), chemical element, rare gas of Group 0 (noble gases) of the periodic table, forming very few chemical compounds. About three times heavier than air, krypton gas is colourless, odourless, and tasteless. Although traces are present in meteorites and minerals, krypton is more plentiful in the Earth's atmosphere, which contains 1 part krypton in about 900,000. The element was discovered (1898) by the British chemists Sir William Ramsay and Morris W. Travers in the residue left after a sample of liquid air had boiled almost entirely away. Krypton is produced on a small commercial scale by fractional distillation of liquid air.

Krypton is used in certain fluorescent lamps and in a flash lamp employed in high-speed photography. Radioactive krypton-85 is useful for detecting leaks in sealed containers, with the escaping atoms detected by means of their radiation.

Krypton gas liquefies at -152.30° C (-242° F) and freezes 4 C lower. When a current of electricity is passed through a glass tube containing krypton at low pressure, a bluish white light is emitted. The wavelength of an orange-red component of light emitted by stable krypton-86, because of its extreme sharpness, served as the international standard for the metre from 1960 to 1983. (One metre equals 1,650,763.73 times the wavelength of this line.)

source: http://www.c-f-c.com/specgas_products/krypton.htm

[Benny]

Ok so it emits UV-C radiation, is that necessarily radioactive?

It says somethin about using it to assist starting in neons, does that mean all neon tubes use the gas or what? And what amount (%) of the gas in neons is the Kr85? It says it emits a whitish blue light, but where does it say that the lamp produces radioactive radiation....

How i interpretted what you were saying, was that the light a UV tube produces is radioactive, not that necessarily the tube contains some radioactive contents..

But i wasnt initially saying it wont affect medicines, i know it does...


But Oxidation cannot happen in an aquarium unless theres electrolysis, and a solid lump of copper somewhere that was what i was trying to prove..

the guy never mentioned medication when he was talkin about copper in the aquarium, i just said that for the record it cant cause oxidation without a solid lump of copper sittin in ur tank...

[Proteus]

when people are referring to copper in the aquarium, they are referring to it in liquid form.

nothing was ever mentioned about a solid lump of copper.

(since you have edited your last reply since you first added it, I wont comment on your original reply, being that it is still on file)

[Benny]

Ok i know its in liquid
Hence i said that theres no oxidation goin on, becoz nobody i know sticks a solid lump of Copper in their aquariums. And yes i know you being the owner of the forum, have acess to the earlier versions of edited messages....

[oscar]

The crux of it is, that the bulb/tubes themselves contain an amount of RADIOACTIVE SUBSTANCE in their construction.

However, when the bulb is operating it emmitts ELECTROMAGNETIC RADIATION, which essentially is light, infra-red, UV, radiowaves, micromaves etc.

To split hairs...
The type of radiation that is emitted from a radioactive SUBSTANCE is called IONISING RADIATION. This is the bad stuff (alpha & gamma rays, and beta particles etc.). Ionising radiation is what the Krypton isotope atoms are emmitting when they are decaying from the Kr-85 down to a stable state. Given that the half-life is ten years, this amount would be negligible.

There is a very important and understandable difference between the two types of radiation.

Anyway, i think we've pushed the radiation cart long enough.

With regards to the oxidation...i'm not 100% sure. I'm to the understanding that solutions can oxidise.

P.S. Sorry for the CAPS.

[Proteus]

Thanks Oscar for putting things into context.

[Benny]

theres a difference between oxidising (reactions with oxygen) and oxidation (an electrolytic reaction)

I figured i would clarify that...

Benny

[Benny]

Ill give a difference between oxidation and oxidising... On all boat outboard motors, there is zinc sacrificial anodes attatched to the motor. Zinc is a shiny lustrous metal, and OXIDISES on its surface, creating a dull matt surface of Zinc Oxide...

However when the motor is immersed in salt water (a conductive electrolyte), the steel in the middle section, and lower sections of the motor want to OXIDISE, ie rust. However the ZINC attatched to the motor, instead acts as an ANODE transferring electrons to the steel, and the ZINC will disintergrate instead of the motor rusting... In the case of the sacrificial anode the zind is NOT OXIDISING but is undergoing OXIDATION, and is instead going from a solid state to an ion state and giving electrons to the steel in the legs of the motor....

Hope that clarified something

Benny

P.S. Proteus i havent intended on treading on your toes with this post, please re read it.. My editing was only because i didnt read all the information you posted up for me. I appreciate you helping explain what you meant by the tubes being radioactive in content, rather then in the light they emit being radioactive.. Cheer up mate, life is too short, no hard feelings.....

[oscar]

Proteus,

How much does turning the units on/off reduce the life. I currently use a couple of the AA Internal units from AOA. Because the inlet is located in the upper region, i have to turn it off everytime i do WC(2-3 per week).

I don't see an alternative? Apart from mounting the unit on its side lower in the tank.

[apalsson]

We seem to have drifted away from the original subject a bit. I was wondering what wattage external UV unit I should get for a 700L tank (6 x 2 x 2).

Ari

[Proteus]

We seem to have drifted away from the original subject a bit. I was wondering what wattage external UV unit I should get for a 700L tank (6 x 2 x 2).

Ari

25 - 36w