Interesting debate.
@pegasus @bang guy
I thought I would speak with a micro biologist.
This was his thoughts.
Here is a couple of exerts from a discussion here in Adelaide where there has been a massive very strong stain of ich present, of which I was unfortunate enough to have experienced.
My thought from the research I have done, is yes they multiply in the sand bed.
So surely if you can catch 30% while in the water column and damage or eradicate them before they get a chance to multiply, you have at least 60% less in the tank during that particular cycle. Thats assuming they double every time they hit the sand ?
Well, I'm going to go against the grain here.
In Adelaide lately there has been an out break of a very strong strain of white spot, my tank included.
My views of quarantining have changed over the years. I started out with a very fancy QT setup and quarantined everything, including corals. In reality I lost quite a few fish in the process. I believe the QT environment is unnatural and is quite stressful, especially if you're going to medicate etc. And it's very difficult with Dragonettes etc.
If and when you end up with disease in your display tank, again I think it's stressful for the fish (and me) to try to catch them out and put them into QT.
In my tank It's not an option to catch them without pulling out most of the rock etc, which will then start mini cycles and uncover anaerobic bacteria etc.
Only other option is do nothing which got me to where I was a few weeks ago. I picked up this very strong strain of white spot so I started to dose Medic. That didn't seem to be working and was very expensive. I researched peroxide and started that treatment but I was losing fish every day. After about six weeks of this I had lost 22 fish. Some I had to euthanase.
I was ready to give up. (Again)
I started phoning other longer term reefers that I knew for some inspiration.
What they all said was get a DeBary UV unit.
I have always been quite skeptical about a lot of these "additional" pieces of equipment believing some retailers are pushing some stuff onto you that perhaps you don't really need.
Anyway, I got one and set it up.
Within 2 days the remaining fish had noticeably less spots. The Purple tang would have died next as he was covered, eyes and all.
Within 2 weeks there was no spots anywhere.
I have left it another 3 weeks before getting any new fish.
I know that UV will not completely eradicate the ich from my system, but it seems to have taken out the vast majority giving the fish a chance to fight.
I have been told that even a healthy fish caught in the wild may have a spot or two, that's all it takes to get into your system, from there they can multiply exponentially.
I reckon if I can control most of them and keep the fish eating and have a healthy immune system they have the best chance that I can give them.
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The De Bary an25e produces 7000mW of uv-c per second.
If you could slow the total flow to allow 10 secs of dwell within the chamber then complete eradication is possible.
I vaguely remember a talk that Pacco from Vebas gave at the cichlid society where he discussed that for UV to be close to a perfect steriliser that flows need to be ramped down considerably. So I would assume that if you had you UV receiving flow from your media reactor that effiency would increase dramatically. The flip side is the time it would take conceivably for the bacteria and or pathogen to reproduce in the aquarium.
Form a different angle - to kill white spot takes 72,000 mW of uv-c, but how much uv-c does it take to damage the cells sufficiently that they are unable to perform their basic functions. UV-C in concentration I believe from biology can cause irrepreble damage to a cell with very limited exposure. With a higher flow rate damaged cells may be exposed numerous times in a given period damaging the cell further with each pass.
High output UV is used on commercial water projects with a very high degree of success due to multi pass of open source waters, aquarium UV have a high probability of success as the closed loop becomes in effect multi pass also.
It is a long time since I played with potable water and biological contaminant solutions; however I think my thinking is on track. Just my opinion.
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Impossible with the De Bary.. Yes, effective in damaging the organism.. absolutely. As stated the reduced flow via a media reactor would seem a good area for low velocity flow.
The other option is to increase the pass thru so that far more water is treated and irradiated numerous time through the day, one would suppose that this would also be an effective method as unicellular, and primitive multicellular organisms do not in general have the ability to repair in the same way as an advanced organism would. It comes back to my point that damaging the organism sufficiently will have the same effect.
Peer reviews of the efficacy of UV in aquaria would indicate that there is substantial gains to be made.
See Here
"Abstract
The virucidal effects of ultraviolet (UV) irradiation, heat, pH, ozone, salinity and some chemical disinfectants on white spot syndrome baculovirus (WSBV) were investigated by infectivity assay using juvenile black tiger prawn, Penaeus monodon. WSBV became completely non-infectious after 60 min UV irradiation (9×105μW s/cm2). The effective concentration for ozone to reduce WSBVs infectivity to zero was 0.5 μg/ml as a total residual oxidant for 10 min at RT.
WSBV was inactivated by contact for 10 min at Room Temp with a final concentration of 100 ppm of sodium hypochlorite and povidone iodine and 75 ppm of benzalkonium chloride. Sodium chloride in concentrations ranging from 0–10% had no virucidal effect on the infectivity of WSBV."
Whilst not completely related to fish an interesting item none the less as over the course of hours and days total exposure to free floating whitespot could exceed 945mw of total exposure.
Ozone as a treatment is also interesting, however my experience with ozone in aquarium is limited having received my unit this week.
Combined use of UV, Ozone it appears may be the best overall solution to removing whitespot over time, however working hard to ensure that it's introduction is limited is a good move.
All these additions cannot and should not replace good practice.
