My Fish Have Mycobacterium Aka Fish Tb. What To Do?

Discussion in 'Freshwater Fish Disease' started by CFish45, May 17, 2018.

  1. CFish45New MemberMember

    A terrible first post to have to make but as the title says, I have mycobacterium as confirmed by a university lab :(.

    I have three lightly stocked 45g planted tanks and I'm losing fish at a rate of about 1 to 2 every month. Before the diagnosis I'd been trying for the last year to fight various symptoms with every medication under the sun to no avail. The symptoms I was seeing didn't suggest fish TB to me at the time but now of course I know they were. The most common symptom I'd see was behavioural changes, the fish would just start acting 'off', generally they seemed to become petrified of anyone going near the tank and would quickly swim away to hide... Before this symptom they'd be out and about in the tank trying to beg for food or trying desperately to mate with one and other :))

    Symptoms like curved spines and open sores were the exceptions to the rule with my fish and were rare enough that they only really happened recently. I've never seen any of my fish with open sores... Only two of countless fish that have passed have had curved spines and even those were nothing like the pictures you usually see for fish TB. The curved spines I saw looked as though the fish had been wagging their tail to swim and had then got frozen in that position.

    I'm now a bit stuck on what I should do next. All of the aquariums have fish still alive in them, and they all look healthy enough (make no mistake though, they are carrying the dreaded mycobacteria). Reading around my options seem to range from culling all of the fish and sterilizing all of the equipment to just leaving them to it. All of the opinions I have read about this seem to contradict one and other leaving me feeling a bit lost. The professor who I spoke with suggested not tearing the setup down because their own studies have shown that this is actually a lot more common than most people think (he didn't elaborate on actual numbers sadly). I'd go down the route of culling fish, sterilizing and starting over again if there was some guarantee that I could get 100% myco free fish, but even with my own best efforts of quarantining fish for 2-3 months I've realized that is probably impossible. The worry is that I'd destroy hundreds worth of plants just to end up here again.

    If anyone here has experience with this horrid bacteria I'd be interested to know what you tried, what worked and what didn't work. I installed an ancient old UV unit on to one of the tanks because I happened to have an old pond unit laying around that hasn't seen use in about 10 years. I've ordered a new quality UVC bulb for it and cleaned the quartz tube but for now it's running with the old bulb in there which could be doing nothing more than acting as a mini algae grow light for all I know! I've also started to remove fish from the tanks the second they start to show any signs of being a little off. Currently they're living in an old plastic storage tub that is heated and lit before I can determine if I need to euthanise them :(. The thought of having to cull the fish and sterilize all of the aquariums fills me with dread; it will be my exit from the hobby if it comes to that because so much work has gone into them over the years it would be soul destroying. I fully realize I cannot save fish once they show symptoms (trust me, I've tried), I just wonder if there is some way the spread can be slowed to a level where I feel the remaining fish are able to live out something resembling a good quality of life.

    Thank you!
  2. maggie thecat

    maggie thecatWell Known MemberMember

    I think following the Professor's advice is the route to go.

    Maintain your tanks. Don't add new stock. Let attrition close down the tanks naturally. Then nuke them by destroying the substrate and plants and sterilizing the tank and hardscape.

    If you decide to set up a new tank, get new nets, and other gear just for it. Use Novasan or other sanatizer after working in the tanks to avoid accidental cross contamination .

    Buy and use disposable dairy gloves to protect yourself from infection.

    I'm sorry you're going through this. :-(
  3. Biev

    BievValued MemberMember

    UV filtration paired with surface skimming is enough to get rid of mycobacterium marinum according to   and my personal experience. You can make a DIY skimmer as shown in  .
  4. OP

    CFish45New MemberMember

    Thank you maggie thecat :)

    I probably should have mentioned I've taken steps to lessen and prevent my own exposure to any of the harmful pathogens by wearing long gloves and washing my hands regularly with hibiscrub but that is a very good point to bring up! I'll despose of all of the equipment when the last fish passes on so that I'm not dooming either myself or another unsuspecting fish keeper to this bacteria. I'd heard that tanks can be sterilized with a strong bleach solution and a through wipe down with a 70%-90% based ethanol solution.

    Biev, that is both encouraging and interesting to hear! I had read the article by Diana Walstad which is part the reason I'd setup that pond UV sterilizer. I'd read other articles full of citations saying that UV was ineffective and could even make things worse which is a lot of the reason I've found myself here confused by the whole thing. May I ask of your own personal experience; how long roughly was it that you started to notice an overall improvement in your situation when you set the UV and skimmers up? For the skimmer setup, does the water that has been skimmed need to be directed into the UV sterilizer? Also can I ask what sterilizers you used? (sorry for all of the questions). I'm potentially going to be looking to buy a couple more for the two tanks to do not have them installed. The pond unit has a 15w tube in it and that was effective at clearing algae in my old pond back in the day. I'm assuming for ~45g aquariums I can get away with a smaller unit. I was looking at 9w internal UV filters for the other two tanks with the view I could always modify them to adjust flow rate and exposure time to the UV light.


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