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WhiteOranda

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Hi everyone!
This is my first post here, thank you for reading.
My black mollies seem to be having an ongoing health problem.

I received a 64 liter (17 gallon) fish tank, it has been running for a couple of years. It was stocked with a black molly colony, a Chinese algae eater, a pair of yoyo loaches (botia) and a bristlenose pleco, as well as a decent amount of live plants. It was obviously overstocked, under filled and under filtered, and a couple of the male mollies seemed to have some type of white film on their faces/heads. Water parameters were okay and I did a 50% water change as well as adding a filter, which ended up replacing the original filter after it was done cycling.

I first rehomed all the bottom dwellers and then tried treating the mollies with Sera Baktopur (water conditioner against bacterial infections (e.g. mouth and fin rot)). There were about 10 mollies and only a couple of them showed symptoms. Then my 26 liter (7 gallon) cherry shrimp tank started leaking and I had to put the shrimp and live plants in the main tank and ended up rehoming all of the healthy mollies.

I was left with 3 black molly males who still seem to be sick. I put two of them in a new 7 gallon (with the old cycled filter from the fish tank), along with a makeshift divider and I left the third molly alone with the shrimp in the main tank. The 3 mollies are very aggressive towards each other so they canā€™t be kept together. I suspect they developed the wounds/fungus/? because they kept fighting each other. I just started treating the quarantine tank with another round of Baktopur and Sera Ectopur (an oxygen releasing salt blend for caring in case of stress and for the effective support of disease treatments against external diseases of fish (e.g. ectoparasites, bacteria, fungal infections)). I am not currently treating the main tank as I fear harming the shrimp.

The tanks are kept at 27 degrees Celsius (80 degrees Fahrenheit).
The main tank is reading CL2 = 0.8, pH = 7.4, KH = 15, GH = 16, NO2 = 0, NO3 = 100.
And the quarantine tank is at CL2 = 0.8, pH = 7.4, KH = 15, GH = 16, NO2 = 0, NO3 = 0.

Please give me some advice if you know how to help the fish ASAP. Should I change the treatment? You can see some pictures of the fish here on Imgur. Thank you!
 
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Hi everyone!
This is my first post here, thank you for reading.
My black mollies seem to be having an ongoing health problem.

I received a 64 liter (17 gallon) fish tank, it has been running for a couple of years. It was stocked with a black molly colony, a Chinese algae eater, a pair of yoyo loaches (botia) and a bristlenose pleco, as well as a decent amount of live plants. It was obviously overstocked, under filled and under filtered, and a couple of the male mollies seemed to have some type of white film on their faces/heads. Water parameters were okay and I did a 50% water change as well as adding a filter, which ended up replacing the original filter after it was done cycling.

I first rehomed all the bottom dwellers and then tried treating the mollies with Sera Baktopur (water conditioner against bacterial infections (e.g. mouth and fin rot)). There were about 10 mollies and only a couple of them showed symptoms. Then my 26 liter (7 gallon) cherry shrimp tank started leaking and I had to put the shrimp and live plants in the main tank and ended up rehoming all of the healthy mollies.

I was left with 3 black molly males who still seem to be sick. I put two of them in a new 7 gallon (with the old cycled filter from the fish tank), along with a makeshift divider and I left the third molly alone with the shrimp in the main tank. The 3 mollies are very aggressive towards each other so they canā€™t be kept together. I suspect they developed the wounds/fungus/? because they kept fighting each other. I just started treating the quarantine tank with another round of Baktopur and Sera Ectopur (an oxygen releasing salt blend for caring in case of stress and for the effective support of disease treatments against external diseases of fish (e.g. ectoparasites, bacteria, fungal infections)). I am not currently treating the main tank as I fear harming the shrimp.

The tanks are kept at 27 degrees Celsius (80 degrees Fahrenheit).
The main tank is reading CL2 = 0.8, pH = 7.4, KH = 15, GH = 16, NO2 = 0, NO3 = 100.
And the quarantine tank is at CL2 = 0.8, pH = 7.4, KH = 15, GH = 16, NO2 = 0, NO3 = 0.

Please give me some advice if you know how to help the fish ASAP. Should I change the treatment? You can see some pictures of the fish here on Imgur. Thank you!
Hi, Iā€™m new to the hobby so will allow more experienced molly knowledgeable members who have helped me such as @Colin_T @speakerman3 to respond more affirmatively, but from what I do know, nitrates at 100 is damagingly high for mollies. Have you done any large water changes since you reduced the stock? If not then the nitrates could be high still from the overstocking, if not then there must be some other cause if you are changing the water regularly, and assuming the tap water tests at zero.
Iā€™ve been taught and have read that good water conditions are potentially the biggest healer and preventer of illnesses.
Iā€™d do a 75% water change in the main tank, ensuring the water is conditioned to remove chlorine etc, and the same again the next day, then test nitrates again the follow day to ensure it is below 20 which is needed for mollies.
Can you treat the quarantine tank with aquarium salt? The other molly would benefit too but I recall (and may be wrong) that you canā€™t add salt for shrimps.
What are the ammonia levels?
The aggression will be due to the mollies being both male. Someone else may offer better advice but perhaps a tank separator is needed.
As I said Iā€™m new to all this so wonā€™t be the best to advise, but hopefully having shared what Iā€™ve learnt recently myself I might have offered a useful start point.
Oh - also to me the photos look to show fin rot. So improved water condition and addition of salt should definitely help.
 
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Hi, Iā€™m new to the hobby so will allow more experienced molly knowledgeable members who have helped me such as @Colin_T @speakerman3 to respond more affirmatively, but from what I do know, nitrates at 100 is damagingly high for mollies. Have you done any large water changes since you reduced the stock? If not then the nitrates could be high still from the overstocking, if not then there must be some other cause if you are changing the water regularly, and assuming the tap water tests at zero.
Iā€™ve been taught and have read that good water conditions are potentially the biggest healer and preventer of illnesses.
Iā€™d do an 75% water change in the main tank, ensuring the water is conditioned to remove chlorine etc, and the same again the next day, then test nitrates again the follow day to ensure it is below 20 which is needed for mollies.
Can you treat the quarantine tank with aquarium salt? The other molly would benefit too but I recall (and may be wrong) that you canā€™t add salt for shrimps.
What are the ammonia levels?
The aggression will be due to the mollies being both male. Someone else may offer better advice but perhaps a tank separator is needed.
As I said Iā€™m new to all this so wonā€™t be the best to advise, but hopefully having started what Iā€™ve learnt recently myself I might have offered a useful start point.
Oh - also to me the photos look to show fin rot. So improved water condition and adoption of salt should definitely help.
Hey, I don't think you being new to the hobby matters, I still appreciate your reply and I think what you wrote makes a lot of sense.

I never had that high of a number show up for nitrates, I will try to get them under 20 tomorrow and continue working on it. I have done a 30% water change immediately after reducing the stock and continued 10% changes daily. I need to test the tap water.
I will be following your advice regarding the main tank.
I dosed Ectopur in the quarantine tank, it is an aquarium salt. As soon as the two fish I have in the quarantine tank heal up I will be rehoming them. Then I will be moving the third final fish into the quarantine tank and starting treatment with aquarium salt.
Unfortunately I have the Amtra Multi Check 6 which doesn't tell me the ammonia levels.
I will try to find a better tank separator, but for now, none of the fish can access each other.
I'm still not sure if it's fin rot. I'm hoping the Baktopur for secondary bacterial infections will be helpful.

Again, thank you for the reply, you helped!
 
Hey, I don't think you being new to the hobby matters, I still appreciate your reply and I think what you wrote makes a lot of sense.

I never had that high of a number show up for nitrates, I will try to get them under 20 tomorrow and continue working on it. I have done a 30% water change immediately after reducing the stock and continued 10% changes daily. I need to test the tap water.
I will be following your advice regarding the main tank.
I dosed Ectopur in the quarantine tank, it is an aquarium salt. As soon as the two fish I have in the quarantine tank heal up I will be rehoming them. Then I will be moving the third final fish into the quarantine tank and starting treatment with aquarium salt.
Unfortunately I have the Amtra Multi Check 6 which doesn't tell me the ammonia levels.
I will try to find a better tank separator, but for now, none of the fish can access each other.
I'm still not sure if it's fin rot. I'm hoping the Baktopur for secondary bacterial infections will be helpful.

Again, thank you for the reply, you helped!
Glad to have helped, if only the nitrates are reduced because of it then Iā€™m sure that will much improve their chances.
I hope someone can diagnose from the photos. I know how frustrating it is when youā€™re trying hard to do right by the fish and not seeing improvements (still going through it myself). Good luck.
 
Glad to have helped, if only the nitrates are reduced because of it then Iā€™m sure that will much improve their chances.
I hope someone can diagnose from the photos. I know how frustrating it is when youā€™re trying hard to do right by the fish and not seeing improvements (still going through it myself). Good luck.
The fish are active, they are taking food and they reproduced (the colony got about 9 babies before I got the chance to rehome them). None of the fish died from the fin rot while I had them, even though one of the ones without symptoms did end up jumping out of the tank as it doesn't have a lid (working on that, as well). Possibly connected to the nitrate levels? Or perhaps it might've happened because I had been using the moon light setting on my lamp?
(I also only had minimal losses with the shrimp (a couple dead ones out of dozens) while moving tanks as the water temperature didn't match and I couldn't drip acclimate them.)

I'm also very sorry about the pictures being so blurry, the fish are acting stressed when I try to take pictures or video, doubly so when I try to use flash.
 
Unfortunately the nitrates are at a toxic level. Please do an immediate 75% water change and daily 50% water changes until the levels become suitable. Focus on clearing out any gunk in the substrate and rinse the filter media thoroughly in dechlorinated water.
 
The jumping very well could have been due to the nitrate levels
 
Unfortunately the nitrates are at a toxic level. Please do an immediate 75% water change and daily 50% water changes until the levels become suitable. Focus on clearing out any gunk in the substrate and rinse the filter media thoroughly in dechlorinated water.
Thank you for the reply!
I will definitely be doing the water changes as well as vacuuming the substrate.
How am I to go about rinsing the filter media? I am aware of the need for cycling tank water and filter media but I'm not knowledgeable about how much filter media gunk I should remove so as not to upset the bacteria in it.
 
What is the media - sponges, carbon, ceramic noodles etc?

Media is usually washed in old tank water that you've taken out during a water change. Sponges can be squeezed until all the gunk has gone. Ceramic media can be swooshed around to remove it. Carbon cartridges can be rubbed and squeezed. Carbon granules can be carefully washed by rubbing the back, but the carbon tends to break up if you are not gentle.

The good bacteria are bound tightly to surfaces in the biofilm so as long as you are gentle the bacteria colonies won't come to harm.
 
What is the media - sponges, carbon, ceramic noodles etc?

Media is usually washed in old tank water that you've taken out during a water change. Sponges can be squeezed until all the gunk has gone. Ceramic media can be swooshed around to remove it. Carbon cartridges can be rubbed and squeezed. Carbon granules can be carefully washed by rubbing the back, but the carbon tends to break up if you are not gentle.

The good bacteria are bound tightly to surfaces in the biofilm so as long as you are gentle the bacteria colonies won't come to harm.
I have a rougher and finer sponge, as well as a small bag of ceramic noodle type things, in each filter.

I've been washing out the sponges in a bucket of old tank water every couple of weeks. It seems I had a grasp on cleaning the filters, but I just had to ask because I really want to help the fish. I will be washing out the filters more frequently and thoroughly. I will probably buy a carbon cartridge for the quarantine tank after I'm done using it.

Thank you for the reply, I am now assured I won't hurt the bacteria colonies!
 
The aggression will be due to the mollies being both male. Someone else may offer better advice but perhaps a tank separator is needed.
This can be the case. When kept in a group, a hierarchy can develop amongst them. Dominant males will chase submissive males . But dominant males can also fight eachother. just to see who's the bigger one in the group. That's normal behavior. But sometimes it can become very aggressive and then you need to make a choice which one stays and which one should leave. But in general, it will pass once everyone knows its place within the group.
 
It sounds like stress from water parameters and aggression were both factors. It also seems like you have received good advice and acted appropriately.

As for cleaning your filters, just shake out most of the sludge in a bucket of old tank water during a water change so that the filter doesn't lose efficiency. The riper the better--until it is clogged.

With a big enough tank and enough tank mates as distractions, molly aggression usually isn't bad. If the 64 liter is what you will have mollies in, it would be best to have one male and multiple females. A lot of live plants will help with aggression, nitrate, and stress reduction while providing shelter for any babies that you get.
 
It sounds like stress from water parameters and aggression were both factors. It also seems like you have received good advice and acted appropriately.

As for cleaning your filters, just shake out most of the sludge in a bucket of old tank water during a water change so that the filter doesn't lose efficiency. The riper the better--until it is clogged.

With a big enough tank and enough tank mates as distractions, molly aggression usually isn't bad. If the 64 liter is what you will have mollies in, it would be best to have one male and multiple females. A lot of live plants will help with aggression, nitrate, and stress reduction while providing shelter for any babies that you get.
Sorry for the late reply, I didn't get a notification for some reason (?).

Thank you for the tips about the filters!

I used to keep mollies in a 100 liter (26 gallon) tank a couple of years back and they never had health or aggression problems. I also assumed the aggression would get dispersed with the 10 adults I kept in this 64 liter (17 gallon) tank, but it was always a problem. I kept lots of live plants and the fish did breed, with a number of the fry getting to sub-adulthood before I re-homed them.



I'll do an update in this reply, as well:

I decided to buy a couple more small tanks, so now the shrimp are separated in a small tank, and the rest of the tanks house a male black molly each. None of the aquariums have more than 20 nitrates. I did the same treatment with the remaining fish. I redosed the aquarium salt with the fish I started treating when I first posted. The fish I already treated seem to be doing better. I got a blurry photo of the fish I just started treating, you can view it on Imgur.

Thank you for your replies everyone!
 

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