HM Red M – Sarawut, originally uploaded by Daniella Vereeken.

Q: A wrote,

After many days of guessing and hair-pulling, I think I finally figured out what’s been wrong with my little guy. I’m pretty sure he has velvet. I checked for velvet already, last week, but I didn’t see anything. And then, two nights ago, I checked him again with a flashlight just for the hell of it, and I saw a yellowish metallic coloring all over his body. I’ve never had any experience with velvet but I’m assuming that’s what it is. I gave him the recommended dose of CopperSafe two days ago and I’m keeping his tank away from light but I haven’t seen any improvement in him yet. He is still lying on the very bottom of the tank barely moving and his coloring is still very brownish. Fortunately, he never lost his appetite…the little glutton! The CopperSafe box says that one dose of the medication is good for a month. Does that mean I shouldn’t give it to him again for a whole month? Somehow I can’t see that being enough to cure him. Do you recommend a different treatment/product for velvet? And how often should I do the water changes now that we know it’s velvet? Should I be doing them more frequently or will that dilute the medication? As always, thanks for your time!

A: CopperSafe is a potent parasite treatment and when dosed properly can be very effective. Like any fish medication, it has its pros and cons. Your question regarding the dosing of Coppersafe is one that often baffles aquarists and unfortunately hasn’t been addressed by Mardel. (At least not that I have found). The Coppersafe bottle says;

“One application treats water for one month. DO NOT overdose.”

Of course no responsible fish keeper would go an entire month without performing one or several water changes. This begs the question, how often and how much should I re-dose? When you do a partial water change you will remove some of the copper medication with the toss water. Replacing some of the CopperSafe may be necessary to keep the medicine at the therapeutic level. Copper, however, is a very toxic and dangerous material. An overdose can be lethal to your fish. For this reason, conservative fish keepers would caution anyone choosing to use a copper-based medicine to also use a copper water test kit. This is truly the safest way to treat with CopperSafe and ensure you are getting the correct level of medicine. My cautions don’t end here though. Copper is more toxic when present in acidic water. Water is acidic when it has a pH less than 7.0. Water with low carbonate hardness (KH) can also create a risky situation when treated with copper-based medicine. KH (also called buffering capacity) is what keeps your pH stable. When KH is low then your pH is more likely to drop quickly making your water acidic. Again, acidic water makes copper more toxic to fish.

So to recap, I will say this… Copper-based anti-parasite medications, like Mardel’s Coppersafe, can work great under the right conditions. It should be used by fish keepers willing and able to test their water’s pH, KH and copper levels. Since you have treated him already, you may want to run a few water tests and if they come out ok, monitor your fish for improvement over the next several days. On the other hand, if you don’t feel comfortable using copper meds or don’t have the ability or willingness to test your water, you may want to consider an alternative like Kordon Rid Ich Plus 37656 – 16oz. or Aquarium Products’ QuICK Cure which both contain formalin and malachite green as their active ingredients.

If our readers have any experience with copper based medications we’d love to hear your stories. Let us know what has worked for you.

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  1. Anonymous says:

    Thanks for all of the information. I did test the water before treating with CopperSafe and all of the levels were perfect. Then I tested again, a day or two ago, after treating with the CopperSafe and both the pH and KH were low. The KH is close to 0 and the pH is around 6.2. Of course, at the time, I had no idea just how dangerous that was until I just read your post. Now I’m completely at a loss of what to do next. I don’t know if I should do a large water change to remove the copper medication of try to artifically raise the pH. And meanwhile, my little guy has been declining the past couple of days and now I know why. This medication is probably doing more damage than the velvet right now.
    Please advise at your earliest convenience!
    Thanks so much,

    • Stephanie says:

      I’ve been treating my betta for about 10 days now with coppersafe because I was pretty sure he had velvet. He’s made a complete turn around for the better. What I did is about a 50% water change every 2-3 days and a 100% water change a few days after that. I’ve heard people say not to do a 100% H2o change, but with velvet you want to keep the water really clean. Treat ur fish for 10 days. Add the coppersafe every time you change the water. It’s 1tsp per 4 gallons. I have a 2 gallon tank so I gave him half a tsp. I did take all his rocks out and his cave so I can moniter him and make sure he’s going to the bathroom. The coppersafe box also suggests to take the filter out because the medication can get caught in the filter and therefore wont be treating the fish; so i took my filter out too. I’m on day 10 of his treatment so his next water change I wont treat the water and will put his filter, rocks, and cave back in the tank. Good luck to you 🙂

  2. Christie says:

    I don’t recommend artificially altering your pH. Large pH fluctuations are very dangerous and can further stress your fish. Fish that contract Velvet usually have a weakened immune system already. You did the right thing by attempting to treat the Velvet disease. Without treatment, Velvet only worsens and leads to death. Because your water is pretty acidic already and your KH is virtually non-existent, you may want to switch to a different Velvet medicine or adjust the amount of Coppersafe you are using. You could also just do a partial water change (maybe 25%) to dilute the CopperSafe somewhat so it isn’t so strong. We know that copper is more toxic in acidic water and we know that your water is acidic so using less of it may still achieve the desired effect. What we don’t know is exactly how much more toxic copper is in acidic water or how it will affect your fish. As you can probably tell by now, there is a lot of guess work that goes into treating sick fish. We don’t have a lot of medical testing or equipment to use so a lot of the time our decisions are based on our best guesses. If you prefer to buy a different Velvet medicine, like RidIch+, do a series of smaller water changes over a day or so to clear out the Coppersafe before treatment.

  3. Anonymous says:

    Hey Christie,
    I tried to send you an email and, for some reason, it will not go through… is your email down?
    Anyway, it has to do with the last email I sent you so I’ll post it here.
    I can’t believe I left a few things out of my last email, here they are:
    The basics:
    1. What is your tank size? 10 gallons, divided, two male bettas
    2. Have you tested for ammonia- what were the results? yes-0
    3. Have you tested for nitrite- what were the results? yes-0
    4. Have you tested for nitrate- what were the results? yes-0
    5. Have you tested for pH- what were the results? yes- 6.5-7.0
    6. What temperature is your tank? 79 degrees
    7. How often do you perform water changes, how much water do you change? 100% water change when amonnia appears (still testing for how many days, just put in a new fish)
    8. What water additives are you using (please include any conditioners, salt or medications) API Stress Coat and TopFin pH decrease
    9. What type of food are you feeding, how often and how much? I alternate between TopFin Color Enhancing Betta Bits, BettaMin Tropical Medley betta flakes, and frozen brine shrimp. I feed the size of their eye’s amount of food twice a day.
    10. What kind of tank mates, when were they added? just two male fish separated by a divider
    11. Is your tank planted? No, just silk
    12. What are the symptoms, when did they begin and is there anything else we should know?
    So, I was very worried about the health of Shelbi and Ember (I named the new red fish Ember) even in the short-term before you could get back to me, so I had to find a solution. They were both very stressed with Shelbi still flaring constantly and Ember shying away and cowarding in the far corner. I went to PetSmart and got a black fish tank background, I cut it to the size of my tank divider. I used a pin to poke holes through the aquarium background (it took me two hours to poke all of the holes!) and then put both the origional clear, plastic divider and the black background with matching holes into the blue divider frame. Now, they can’t see eachother- this has made a huge difference! Ember has perked up tremendously and is twirling around beautifully in the tank. He is much more outgoing than I expected and seems healthy.
    So now I only have two questions:
    The bunched up fin question (in last email)
    What do you think about dividing tanks? (in last email)
    THANK you SO much for all of your help and next time, I promise I’ll try to limit it to ONE email 🙂
    Have a great day
    Becky S.

  4. Christie says:

    Hey Becky, The curling you are seeing is usually caused by healed fin tissue most likely from fin rot that the fish had some time ago. Sometimes when a betta looses his fin tissue, from fin rot or injury it will grow back and not look exactly the same. It can be a slightly different color or even curl like your betta. Whatever the cause, your fish looks completely healed and healthy now. As for divided tanks, I think they can be a great way to keep multiple bettas. There is a risk that one fish will make its way over to the other side. I personally have had some trouble. I actually had a female kill my male, fiercly. I found my male dead with no fins and the female swimming on his side of the divider. This doesn’t mean it will happen to you. I know lots of people who use divided tanks with their bettas without issue. Just check in on them every day.

  5. Anonymous says:

    Thank you 🙂
    Shelbi had stopped flaring at first when I put the black background in the divider but, even though he can’t see the other fish (Ember), he as started flaring again, do you think this will slow down eventually? I think he can sense the water movement caused by Ember so he knows that there is a fish on the other side… is this possible? It seems so strange that he would flare at something he can’t even see…
    Let me know your thoughts 🙂
    Thank you, thank you, thank you,

  6. Anonymous says:

    How long does it take to treat velvet with coppersafe? I havent seen any improvement after 1.5 weeks..

  7. Fish Tanks says:

    Thanks for these tips. I once used CopperSafe and did end up overdosing my Betta. Are there any alternative methods or medicines that you would recommend? Since I didn’t have success with CopperSafe the first time, I’m nervous to use it again is necessary.

  8. Sumer says:

    I need help fast. I think my betta has velvet only because he fits all the symptoms except I really dont see the gold or rust color. I though I saw some gold by one of his fins but it does not cover his whole body. I used Coppersafe yesterday and after reading all these posts I have a feeling I am killing him. I am going to do a complete water change but I am at a loss on what to do next to help him. Do you always see the gold/rust color? Is there anyone else with this same problem? Please someone help me and Blue!!!

  9. Goldfish Care says:

    Very informative post on CopperSafe. The biggest thing when using any fish medication is to follow the recommended dosage. More is not better!
    If people follow the information provided, they shouldn’t have anything to worry about.

  10. Anonymous says:

    My Betta fish Finn got velvet and I went to Petco for some meds. They were very kind. and stupid, Kind and Stupid. Then I went home , with fungas treatment in my hand 🙁

  11. Stephanie says:

    Can coppersafe cause fin rot? My betta is on his last day of treatment for his velvet, but I just noticed today that his fins are looking a little shaggy and straggly. Anyone have some suggestions? I don’t really want to treat for fin rot when he’s just getting done with another treatment, but if it’s a must, its a must.

    • Christie F. says:

      Stress or secondary infections caused by the stress of Velvet Disease can lead to fin rot. I’m not sure if Coppersafe can cause it.

  12. NewsView says:

    Velvet, Costia and Ich can kill quickly and often attack every member of the tank whether the symptoms are apparent or not so the key to success with any treatment approach is early intervention. If you’re considering using this product and aren’t sure how your fish will react, my suggestion is to dose for half your actual tank volume (not to be confused with its overall capacity!) and increase to the full dose over the following day (or two).

    Although you can read a lot online about what does or does not work for a sick fish, such reports are generally anecdotal. If you suspect a particular illness a better approach is to consult the Merk Veterinary Manual (available online), which will indicate only proven/established medications for a given condition.

    Some people recommend salt and/or heat but my own experience with those methods is mixed. For example, Ich, flukes and Velvet often attack the gills — which means if you raise temperatures, fish with gill damage will have an even harder time breathing because oxygen saturation drops in warmer water. Similarly, you won’t read very many reminders that salt and/or ~86-degree heat is not safe for all freshwater fish. Moreover, if you go online and read up on the use of salt in freshwater fish diseases is that many guides don’t even bother to stress that table salt is typically supplemented with Iodine — and Iodine will kill your fish! Complicating matters, there is evidence that while using heat to speed up the life cycle of Ich is effective, killing Ich may require temperatures above 89 degrees — and most fish cannot tolerate those temperatures! (And, in the meantime, because you have cranked up the heat, the Ich will attack your fish that much faster because their reproduction cycle speeds up.)

    Removing the carbon filtration, as most medications require, is also problematic unless you do water changes every day (or at least every other day). Water changes, however, mean re-dosing. Unfortunately, re-dosing a medication more “art” than science. Chances are, one will either under-dose or over-dose but probably never maintain the correct dose if water changes are conducted during treatment (particularly a weeks-long effort).

    Having said that, what makes copper-based treatments so very effective in eliminating a broad range of parasites is also what makes such treatment risky: they’re toxic. On the flip side, however, treatment-resistant parasites are one of the problems associated with using less-than-ideal medications/methods.

    A common issue with alternative parasite medications is that they fail to specify the correct duration of a treatment for one type of infection vs. another. Product labels typically indicate that you do one or two treatments. However, using gill flukes as an example, it will take a month of treatment using the popular PraziPro to knock it out — yet the product label implies that a single course is generally sufficient (setting up a scenario wherein treatment fails, fish die and the parasite potentially develops resistance — not because the medication was “bad” but because the instructions for how to eliminate a particular type of infection are lacking).

    In the end, those of us in the fish hobby have to weigh the pros/cons between “toxic” medications and safer, gentler options. When dealing with this type of medication, which persists longer in the water, adding in medication to account for medication removed by water changes means you are extending the activity period of the medication every time you re-dose, which may set your fish up for what ends up being a 60-day treatment!

    For my money — and I speak from experience as someone who has wasted valuable time treating fish with alternative (newer) products that failed to knock out the problem — the benefits of Coppersafe outweigh the risks. With Coppersafe, a single treatment lasts a month so it is much more convenient. With Coppersafe you’re not losing your carbon filtration. With Coppersafe, you aren’t stressing the fish out doing 2-3x the number of water changes as you normally would for upwards of a month. With Coppersafe, you’re not re-dosing medication to account for a water change so it eliminates the guesswork.

    My take is that when fish are stressed by parasitic disease keeping things “quiet” — and dark if Velvet is suspected — is key. Part of keeping things quiet is to minimize disturbances to already-sick fish — which catching a fish for a medicated dip and/or daily gravel-vacs can do. So to answer the previously-mentioned concern that going 30 days without a water change is unrealistic or irresponsible, yes you can go that long providing you do a large water change right before you start the treatment.

    To speak to the more general concern about water changes: I have maintained a freshwater aquarium with once-monthly (40-50 percent) water changes for over 25 years and in that time I have not only had success but very long-lived fish. (My pictus cat made it to 14 when the info online says they live only about 8 years. I currently have a pleco going strong at 13 and I had a goldfish that made it to 16 and would have lived longer had I not had a heater malfunction that “cooked” it in 84 degree water.)

    The only “secret” I have as a long-term freshwater aquarium keeper is to under-stock the largest tank you can afford with the fewest amount of fish you can tolerate and to run a filter designed to handle a tank at least a 50 percent larger aquarium than it’s actually servicing (in other words, don’t buy a filter that is adequate for your tank size — run one that is more than adequate). With this setup you can indeed go a whole month — but not any longer! — between ~40-50 percent water changes.

    In summary, Coppersafe treatment for a month is a “one and done” solution that doesn’t require you to pull your filter apart. More importantly, it’s among a small number of anti-parasitic medications that will do the job when you’re not 100 percent sure what kind of parasite issue you’re dealing with.

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