UV flow rate - help needed please - ich "management".

[BigPhatReefer]

Hi,

I have purchased an external filter within built UV to hopefully help manage a current outbreak of Ick until I can get a separate hospital tank up and running - as this needs a proper cycled filter, lights and decent amount of decor it will tank me a month or so to get this all sorted out (I think people under estimate the importance of this being a good home for your fish for the next 3 months).

I was looking for some advice on the use of UV.

To my understanding UV's are generally used for algae control and the water passes through the UV section too fast for it to effectively manage ick.

My maths based on needing to reduce the flow rate by 2.4 (has anybody got any thoughts on this 2.4 figure??) as quoted on the DD website.

Flow rate 1400
Divided by 2.4
Required flow 583.3333333
Flow per minute 9.722222222

Filter specifics:

Suitable for Tanks up to 600 Litres
Flow Rate: 1400 Litres per Hour
Hose size: 20mm / 0.8" Outside, 15mm / 0.6" Inside Diameter
Hose length 1.8 Metres
Water Volume: 12 Litres (Approx.)
Power: 30w
UV Power: 9w


620 Litre clearair maz 1500 (inc sump)
Ever grow LED + T5 bulbs
Bio Pellets reactor
Deltec Skimmer

Alk 10
Calc 450
Mag 1400
Pho3 - some.
N02 - Nill
NO3 - trace

 

[Spar]

the issue with UV and Ich isn't just limited to exposure time. It is the fact that most of the parasites (regardless of stage) are unlikely to ever even go through the UV at all. They are attached to the fish, crawling on substrate and/or attached to the substrate. They wait out a swimming fish to come near and then go for it. Yes, plenty will still go through the UV and possibly die, but not even nearly enough to make any kind of dent in the population unfortunately.

To speed up your QT, just use a bacteria additive like Seachem Stability or whatever is available in the UK specifically. This will get your bioload ready almost immediately.

Having complete "comfort" for your fish for the 3 months just isn't necessary, which is why most people keep QT's as a bare bone setup, using PVC for hiding places rather than rock, etc. The only parameters you really need to monitor are salinity, temperature and Alkalinity for this tank.

What is your treatment method planned for the fish?

I know my response is dodging your UV flow rate question, but hopefully helps with your plan.

 

[BigPhatReefer]

It appears to be 50/50 whether UV helps for different people with differant tanks.

I've done the research and using a UV is an option i want to persue - i need advice on flow rates not anything else at the moment thank you.

Is 9 watts powerfull enough? It feels on the low side...

 

[Spar]

you would need a nuclear reactor for it to actually kill the parasites that stay confined in your display tank (never even bother going down into your sump), meaning it doesn't matter what wattage UV sterilizer you utilize, the parasite will remain. i'm sure 9w's is plenty for killing the unfortunately few parasites that actually pass through it.

as for flow, the slower you go the harsher it is on what passes through it. meaning it will start killing beneficial things as well, namely things your coral want/need to feed on. (...assuming you have coral anyway...?). I'd personally be hesitant to lower it as low as a 2.4 factor, but you would still be having a healthy flow of water going through it (i.e. 584 lph is still reasonably fast), leaving very little time for each organism to 'cook'.

perhaps just try this for a short period of time and look to see how your coral (again I am assuming here...) responds. I don't foresee any negative impact on the fish at all, so you should be good there. yes, the UV will kill beneficial bacteria, but your tank is crawling with plenty of bacteria all throughout it, enough that there won't be a negative impact to the point of seeing a spike in ammonia... never hurts to monitor it closer though.

I'd stick with the recommended sized UV sterilizer, especially since you are considering reducing the flow by a factor. if you go stronger and slower you are going to start cooking things too much.

 

[BigPhatReefer]

Can i ask a rather direct question - is any of this based on experience? Have you ever used UV to attempt to manage ich?

Its fairly obvious its just a "technique" that you wouldn't use - and you are more than entitled to that opinion.

I'm not expecting a miracle cure - but it certainly would be good if it could just reduce the amount of the parasites in the water column until i can organise a full treatment.

Some of the fish haven't been in there long so its concerns me that i'm pulling the full tank apart before they've had a chance to settle in - so stressing all the fish because two are showing symptons might be a poor choice until they've had a few weeks.

I've conducted some further research and 9 watts is woefully under powered for a sensible turn over for the tank - i need closer to 36 watts which will allow a sensible amount of flow.

So i guess i have answered my own question in the mean time!

The external filter is going back to be replaced with a stand alone UV and a pump.

I will install the equipment and let you know 1) if it made any difference and 2)if there where any negative effects.

 

[BigPhatReefer]

Update to the situation...

Is there a sweet "Watts per litre (per hour)" figure that will be effective in killing ich but not doing to much in the way of negative effects?

 

[Spar]

Can i ask a rather direct question - is any of this based on experience? Have you ever used UV to attempt to manage ich?

Its fairly obvious its just a "technique" that you wouldn't use - and you are more than entitled to that opinion.

I have used UV, yes, but not for the purpose of helping with Ich, so I don't recall if I had it powerful enough or not. Regardless, back then I always had Ich, so I suppose it is based on some experience to support that it did nothing for me (in terms of Ich).

My statements are based on having an in-depth understanding of the life cycle and behaviors of the parasite itself. Ich does not act in a manner that would guarantee, or even encourage, it to flow through the UV light at any point during its various life cycle stages. UV only attempts to kill what passes directly through it, it does nothing for anything else in the tank.

When Ich tomonts are released (theronts), there are hundreds to thousands of them released all at once, scattering all throughout the tank. And there are a plethora of tomonts, so multiples of this are all occurring all the time. Yes, several/many/most perhaps will find their way to the UV, but it is just statistically improbable that you would ever see close to a 100% success. Some will find a fish, thus continuing the life cycle.

There are other benefits of using a UV sterilizer, such as water clarity, so I'm not saying "it is a waste of money/time". I am just saying that you will have to have some other process for ridding the tank of Ich for you to have a parasite-free environment.

 

[ThRoewer]

UV is only of use for two things:
A. limit the spread of diseases from one tank to another connected tank.
B. control algae blooms

The UV devices you usually find in fish stores are of low wattage and only suited for purpose B but too low in power to reliably kill parasites or bacteria that come through it.

For purpose A you need at a minimum a commercial 250 W unit.
And again, it only limits the spread of diseases, it isn't a way to cure them.

 

[BigPhatReefer]

Just like to say... it worked! Bye bye white spot.

 

[JustinM]

I’m happy to hear that you haven’t seen any more ich but what you’re likely experiencing is that the strain you had has died off. If no new strains of ich were added, the ich will out compete itself in about 11 months time. UV does help some but it did not eliminate ich for you. Nutrition, husbandry, and time was in your favor Happy reefing!

 

[BigPhatReefer]

It died off within a month or so (at least visibly) - i just don't come on here very often!

100% agree... all most entirely down to nutrition and removing stress, not going to achieve anything on its own, but part of a "tool kit" it is worth considering.

 

[Superpuma]

Question you asked early doors.

UV flow rate of 200 liters / hour for every 10watt of uv, tank volume through uv 1-2 times per hour. It's worked in the past for me too, though it's far better to have the supply pump for the uv hovering just over the sand in the display.
Mike