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Author Topic: Melafix - a warning about Pencilfish  (Read 10194 times)

Offline psymongreen

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Re: Melafix - a warning about Pencilfish
« Reply #15 on: February 09, 2011, 04:12:27 pm »
That's all I was after - a caution note on the label for pencilfish.

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    Offline billko

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    Re: Melafix - a warning about Pencilfish
    « Reply #16 on: February 09, 2011, 04:24:49 pm »
    I dont think it was meant to be unprofessional or flippant, i think it was just used to try and get a point over and unfortunately it can be true with regards the net...the bad reports tend to be a bit disproportionate simply because no one seems to bother putting the good results on here. I have heard on more than one occasion of others apparantly having problems when using it with Pencilfish too but other than their actual report and their references to existing reports already out there on the net no one seems to be able to say for definate that the two are linked where as the company in question tell us they are aware and have done all they can to try and find out if there is a problem and upto now have not been able to. Personnally i think it's a respected company that have at least acknowledged that there 'could' be a problem and apparantly have not simply chosen to ignore it or deny any possiblity of it, maybe a warning of 'possible' problems on the box might be an idea at least until it's 100% certain one way or an other.

    I agree with John and think he makes some good points
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    Offline AndyGordon

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    Re: Melafix - a warning about Pencilfish
    « Reply #17 on: November 15, 2011, 09:57:39 pm »
    Lots of people on lots of forums have had a problem with pencilfish and Melafix. Check google

    Also when Melafix was scientifically tested by a professional vet who specialises in fish he observed that it had absolutely no antibacterial properties at the recommended dosage.

    Melafix is promoted to have antibacterial properties but our research has shown this is not the case. We treated an inhabited system for five consecutive days and then ran CFU (colony forming unit) tests on the water and found a typical population of Aeromonas hydrophila/caviae, and Citrobacter freundii, as well as Serratia spp.

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    Offline TommyTopTetras

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    Re: Melafix - a warning about Pencilfish
    « Reply #18 on: May 02, 2013, 02:59:07 pm »
    Hi guys,

    official response:

    Hi Simon

    I'm sorry that you have had this horrible experience. Mars Fishcare (MFC) have done a lot of research on Melafix and pencilfishes. The usual tests were carried out as part of the development of the product, and they did not show any problem with pencilfishes and the product. At some point after that, someone raised this idea of it being harmful to pencilfishes, so MFC did extra tests. These also showed no problem. The question was asked as to whether there could be some unknown factor about keeping pencilfishes in a tank in someone's home that couldn't be replicated in the lab. So MFC recruited a series of hobbyists who kept pencilfishes in their tanks at home, and had them use Melafix in a trial. This also showed no problem.

    You probably can get a lot of hits if you put this problem into Google, but then you would probably also get a lot of hits if you put something like "I was abducted by aliens" - such is the nature of the internet. Once an issue gets to a certain level on the internet it becomes self-sustaining like this. I appreciate though, that this info doesn't really help you very much at the moment. I can pass your comments on to the head of API, Gary Jones, if you wish, so you will at least be sure that they have been heard.

    I've not had a chance to reply to the mail yet, as I've been off - not feeling so good myself. I've only got 2 pencilfish left now, both in the QT. So far I've not managed to get either of them to eat anything since they have been in there, so not holding out much hope for them either. Both are just staying in the same place - about 1 inch off the substrate and not moving much. All my other fish are fine.
    Sorry to hear of the problems you have had and the official response seems to be  that it's perfectly safe  to use on these fish.
    Just wondering if any other folk with pencilfish on the forum have used Melafix without any issues.


    Just looking at this letter I am appalled at the response simply shrugging off the problem saying all the internet research is false because you can write anything on the internet.

    Yes you can.

    But, if people start to notice a problem with for example a particular chemical on a particular fish - this is exactly the grounds that scientific trials are based on.

    I would like to know if the Mars Fishcare are prepared to publish their trials they have carried out specifically with Metafix and pencilfish (if they actually have done any at that time) so they can be scrutinised the same way medical trials are.

    Without knowing what they did we don't know whether their tests recreated domestic conditions with normal fish and their recommended use of the chemical.
    Pharmaceutical companies use all sorts of tricks to improve the appearance of mediocre and even negative results including:

    Simply binning the results of certain trials that didn't end up saying what they wanted and only using the trials that came out on top often by chance or lack of proper control.
    Playing with the dosages (lets give the strongest dose of one drug and the minimal dose of our drug and test which one has the worst side effects...)
    Bias - Doubt this is ever controlled in aquatics but could have an effect
    Controls - all of the variables in fishkeeping, were they controlled or manipulated by design for an unrealistic false positive.

    All of the above are applicable here so I think it pretty insulting to hold all of those cards and say 'it weren't nought to do with us'.

    At the very least recognising that there is the potential for there to be a problem and applying a cursory warning is the least they could do, I mean we can't expect them to test their products on every single fish on the market but the evidence here seems stronger than for example that of the MMR hoax that managed to sweep the nation.

    Unless of course I am wrong and this is all published somewhere and I am just too ignorant and lazy to bother finding out (quite possible!)

    big sigh - rant over!

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    Offline geoffkemp

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    Re: Melafix - a warning about Pencilfish
    « Reply #19 on: June 02, 2013, 07:36:01 am »
    Wanted to add that, I have run Melafix on a number of tanks, with a variety of species of Pencils in, of the top of my head, the species were N.Beckford, N.trifasciatus, N.marginatus and N.mortenthaleri and I don`t recall any problems related to Melafix or Pimafix. 


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    Re: Melafix - a warning about Pencilfish
    « Reply #20 on: August 23, 2013, 06:54:08 pm »
    This is an absolute tragedy for you, Psymon.

    If you reverse the question then how many people have had a good response from Melafix with their pencilfish? It would be interesting to see if there are more or fewer.

    With any new human drug being trialled that makes it through into the general medical use, there is a feedback loop where doctors must report otherwise unknown adverse affects. Drug companies know very well that they cannot simulate every single permutation in the lab and on the small number of human samples that they use and whilst they can test a drug safety with regard to dangerous side effects, they rely on feedback from the medical profession when the drug goes live. I'd be very surprised if manufacturers of animal treatments aren't governed by the same rules/guidelines.

    I am surprised that the manufacturer is so dismissive. In my humble opinion, a better line might have been to say that she would take this back to the company for further investigation.

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    Re: Melafix - a warning about Pencilfish
    « Reply #21 on: September 05, 2013, 06:05:38 pm »
    I'd be very surprised if manufacturers of animal treatments aren't governed by the same rules/guidelines.

    They are. On the official side, every complaint of fish loss that the consumer believes is associated with a medication has to be reported to the relevant authority, and the manufacturer has to submit their data which shows the safety of the medication with that species. This is a condition of the licence. Most consumers are unaware of this.

    On the unofficial side (speaking for Mars Fishcare, anyway) all feedback is shared within the company and across international boundaries. There is a group of people who deal with technical consumer questions and problems in each office, and we are all in constant communication.

    I am surprised that the manufacturer is so dismissive. In my humble opinion, a better line might have been to say that she would take this back to the company for further investigation.

    I'm struggling to see how that relates to what I wrote. (Which, incidentally, was a private email between two people and not a post on a forum or a 'press release' - I don't mind Psymon pasting it here but I think it's important to remember that). I wasn't in the least dismissive, I explained what had been done and why I believed the medication was safe, and I offered to pass his experience on to the highest level. I think that people are just using this long-running thread to rant against companies without actually researching any of it (for example, AndyGordon's post here back in Nov 11 was wildly irrelevant - it had nothing to do with the topic, it stated that Melafix doesn't do something which it is not designed to do and never has been, and it linked to an article by an independent vet who actually said he had trialled it, it was safe with all species and it was the most impressive treatment for bacterial sores he had ever seen - yet no one has called any of those things out).

    Wanted to add that, I have run Melafix on a number of tanks, with a variety of species of Pencils in, of the top of my head, the species were N.Beckford, N.trifasciatus, N.marginatus and N.mortenthaleri and I don`t recall any problems related to Melafix or Pimafix. 
    This is of course what you would expect, but for that very reason no one will start a thread on the internet saying that!

    Offline Unseen

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    Re: Melafix - a warning about Pencilfish
    « Reply #22 on: September 05, 2013, 06:19:39 pm »
    I found the abducted by alien bit condescending. I agree that anyone can write anything on the Internet, but it still is a case that a few on here have had this problem. Perhaps your water conditions and theirs at the time will give some light on the issue also?

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    Re: Melafix - a warning about Pencilfish
    « Reply #23 on: October 20, 2013, 12:18:03 am »
    I agree, it does come across as a bit of a brush off. I must admit I use melafix (don't have pencil fish), simply because the local fish store recommended it some years ago - I'm ashamed to admit I have no idea at all whether it is actually beneficial at all. I just dose the tank occasionally if a fish is injured and every other water change basically because I was told to.
    « Last Edit: October 20, 2013, 12:19:59 am by Zenemu »

    Offline lurch1000

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    Re: Melafix - a warning about Pencilfish
    « Reply #24 on: October 20, 2013, 12:49:22 am »
    I'd not call it a brush off. It's maybe not comparable for fish keeping, but it's a very valid point. Only bad things get reported, don't give tubifex to fish, they'll get parasites. Find one thread on the internet titled 'I gave my fish tubifex and no parasites'. You'll be lucky if you find one.

    Dig enough on any medicine, human or pet, in some cases, there will be an adverse effect, is it coincidence? Who knows. All we can take from consumer reports is that we need to make our own decisions. A company like Mars/API isn't going to put a medicine out with proven adverse side effects, it's damaging for business.

    Having been in communication with Anna to discuss a technical query over another product, inhave to say the level of attention given, and explanations given was first class. Certainly gives me faith in API products. Let's face it, which test kit do most hobbyists use as a general all rounder?

    So, not to takeaway from the OP's problem, but new fish in a tank and adding meds so soon? Could well be a set of concurrent events that triggered the deaths. It's possible that adding the Melafix did kill the fish on this occasion, but had the Melafix been added to the same tank with the same fish a good while after the fish had been introduced, the outcome may have been different. I'd be interested to compare the OP's water to the 'ideal' water to pencil fish. Keeping a fish too far removed from it's intended parameters may have an adverse effect anyway, although that could probably use some citations.

    The sticky is worthwhile, caution should be taken when using any medication, and the more sensitive (for want of a better term) the fish, the more care should be exercised when medicating.
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    Offline Babblino

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    Re: Melafix - a warning about Pencilfish
    « Reply #25 on: June 15, 2015, 01:15:17 am »
    Does this apply to all pencilfish? I have dwarf pencilfish (nannostomus marginatus) and ive been using melafix antibacterial with their tank with no casualties at all.
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    Offline plankton

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    Re: Melafix - a warning about Pencilfish
    « Reply #26 on: June 15, 2015, 09:34:03 am »
    I think it does depend on how much is used, and which pencils are involved, but many types of pencil do appear to be susceptible to it for some (obviously) obscure reason.
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    Offline Tmoralez

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    Re: Melafix - a warning about Pencilfish
    « Reply #27 on: April 07, 2020, 10:50:55 am »
    Thank you. I wanted to get 2 female bettas and glad I saw this post. It's hard to know everything about fish. To be honest it makes me feel better knowing I'm not the only one fxcking up lol. There's no guidebook for every single detail.  :458:

    [Lquote author=psymongreen link=topic=19218.msg228043#msg228043 date=1297034206]
    A bit of history first...

    On Friday, I had one Prestella tetra with a lump on its nose and a pencilfish that looked like it was missing some scales. As per one of my other posts, the male pencilfish like to rub against each other in a Daft display of macho.

    On Saturday, I decided to get a qt for the Prestella, in case it was ntd (as per previous post) and also some anti parasite meds. Started running the new filter in my main tank ready...

    Sunday, in lfs for some RO, it was suggested that adding more female pencilfish may help stem the aggression between the males a bit. Also, the Melafix that was recommended for the tetra would be good for the pencilfish scales.

    Straight home with RO, heater in ready... The plan was to do a 25% water change on my main tank, and to put some of that in the qt tank, along with the filter. Thought it should help get the qt up to speed quicker as tank water quality is pretty good. Then, add the RO like normal to my main tank.

    Later, back out for 3 more female pencilfish...

    So, I decided that I'd try the Melafix before moving the Prestella to the qt as according to the instructions it is safe for all aquatic species - even sensitive ones.

    Anyway, I add the 3 pencilfish as per the way I've added all my fish so far and all looked ok.

    Added Melafix as per dose instructions...

    5 mins later, I've got a dead pencilfish. I put this down to being new - maybe ph shock? I was a bit worried as I'd not had this before. I also noticed 2 more near the top. I thought, uh oh, I just got a dud batch from lfs. Should have been okay though - it was the same batch the other 6 had come from 2 weeks previous...

    Sure enough, with in a couple of mins both fish had started to spiral and ended up on the bottom, not breathing.

    Then I noticed pencilfish number 4 dead on the bottom and 1 more at the surface like the first lot. At this point, I pulled all the remaining pencilfish out of my tank over to the qt. Unfortunately, it was a not slow.

    At this point in time, out of the 9 pencilfish I had, only 3 are now alive, and I don't think one of them will make it until morning.

    I did some Google research on Melafix - loads of forum hits like the one I'm writing here. For some reason, Melafix is fatal to pencilfish. I will be writing to MARS to make sure then add a warning. Apparently, it effects Bettas the same way. No such warning on the bottle though - even though lot of people have found out the hard way like I just did.

    I'm glad a did Google though - as a loss of 6 (probably 7) fish in 1 day has made me feel awful. It made me feel a bit better knowing it wasn't my water quality that had done it - I just wish I had done more research on the 'miracle' blue bottle everyone raves about  :(

    Just thought I'd pass this one - it might just save some fishie lives...

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