I have a turbotwist uv sterlizer in-line with my canister filter outlet. My question is how long should I keep my uv sterilizer on? If it kills parasite and bacteria won't it kill the good with the bad? Right now i've just been turning it on for a few hours when I get a new fish.

Just turn it on when youre putting new stuffs in your tank. Turn it on for 3 days when you clean algea from your glass. Remember to replace the UV after 6 - 12 months. Cheaper to buy a new UV than replacing the UV tube.

For me i will on the UV 24/7 . For a coralife turbo twister it still cheaper to can the bulb than the whole unit.

lots of nonsense advice on UV lights.
the right way to use UV is to get a timer...presume yours is 4 footer tank ...let it run for 45minutes a day....daily.
yes it will kill the good and bad bacteria, but if your filteration system is good enough , the good bacteria will reproduce itself,...the main object is to reduce the bad ones.
45minutes will get 2 turnovers on a slow pump.
UV is not something to mess around with if u dont know have a full understanding of its fuction....skip this , most home marine tanks will do fine without it.

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Funny, I thought the 'good' bacterial you want stays in the filter bed, so how can it get 'killed' by the UV device?
Those that stays in the water ( good or bad ) gets kill I was told.

Cheers!

BT Lee

funny rite....filter beds only when u use undergravel plates...even that water current still pass thru and bad bacteria do stay in filter beds as well. suppose its a cannister filter, how do u explain that?
yes,those that stay in the water good or bad will get killed, but u could always replace new good bacterias....once a month...as i said the main object is to reduce the bad ones.

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Dear Ari,

My understanding is that good or bad bacterial get killed as they pass the UV light.
So, only those that is water bourn and gets unlucky enough to go pass the UV unit get killed.
Those in the filter bed, under-gravel or canister will not be effected.
I suppose, it is the good bacterial in the fiter bed ( again under-gravel or canister or sump ) that is doing the significnat part of the work converting ammonia to nitrite and to nitrate.
As to the bad bacterial in the filter bed, no harm to the fish directly if they stay in the filter bed and the fish do no stay in the filter bed.
If they get out of the filter bed, depends on their luck lah.
If they gets stuck to the fish before they go pass the UV filter, the bacterial win.
If they go pass the UV filter before they get stuck to the fish, the UV filter win and the fish gets lucky.

I suppose this is only theory.
No way to proof that it works.
Just have to trust the manufacturer's recommendation.

In my case, bought 2 China made unit with no operation instruction at all.
Like to hear form other user who has been successful with its use.

Cheers!

BT Lee

What is this "bad bacteria"???

I think what you mean is the parasites in the fish.

When you introduce new fish, it usually has some parasites from the wild. Most parasites spread by releasing "babies" into the water column to infect other fishes. If you have healthy fishes, they can defend themselves. If they are weak, they will be infected. These parasites will die out if they don't have a host within a period of time.

As these parasite spreads through the water column ... no fish in sand, so they don't really populate the sand or filter ... the UV filter will kill them. Even if they are in the sand or filter, they will die naturally without a fish host.

Hope this helps.

yar agree...no point figuring out how they work..as long as they are doing their job and we get what we want.
I use Uv for all the tanks i setup..sort like add more equipments to mark up the price.
but uv do help in producing crystal clear water, i even install uv for my fresh water setups...but overdoing it would create more trouble then it really has in the begining. thats why a timer is important...just let it run a few hours a day.

if ozone is used, i would skip uv all together.

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...or turn into spores and live to infect another day!

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