White spot on Black Molly just appeared
- Thread starter IcePac
- Start date
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If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
Please take a read through the "unhealthy fish" sticky, and give as much detail as you are able to the questions.
https://www.aquariumadvice.com/forums/f17/before-posting-about-unhealthy-fish-read-this-32451.html
https://www.aquariumadvice.com/forums/f17/before-posting-about-unhealthy-fish-read-this-32451.html
OK... I read the sticky and there is a lot of questions about tank size etc, but I guess I was hoping the photo might be self evident to those who are experts.
The Molly shares the 10 gallon tank with some red line endlers, harlequin rasboras and cardinal tetras. The water seems fine and the other fish are all happy.
I notice the elders keep going to the spot on the Molly to eat it.
The Molly shares the 10 gallon tank with some red line endlers, harlequin rasboras and cardinal tetras. The water seems fine and the other fish are all happy.
I notice the elders keep going to the spot on the Molly to eat it.
Its like going to the doctors. You get asked a lot of questions that you might not see as relevant, but are important for a diagnosis and determining cause. Without information its very difficult for people to say whats wrong. The photo is helpful, but on its own doesnt tell us much.
Things like "water seems fine" isnt of any help because we have no way of knowing how you have determined its fine, or what you consider fine. If its something you dont know then inform us you dont know and we can advise on how best to find out.
Things like "water seems fine" isnt of any help because we have no way of knowing how you have determined its fine, or what you consider fine. If its something you dont know then inform us you dont know and we can advise on how best to find out.
Last edited:
Colin_T
Aquarium Advice Addict
Hi and welcome to the forum 
The white mark is excess mucous covering a fairly large wound. The fish is also covered in excess mucous, which suggests something is not right with the water quality.
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Check the ammonia, nitrite, nitrate and pH of the water. Then do the following.
Wipe the inside of the glass down with a clean fish sponge. This removes the biofilm on the glass and the biofilm will contain lots of harmful bacteria, fungus, protozoans and various other microscopic life forms.
Do a 75% water change and gravel clean the substrate. The water change and gravel cleaning will reduce the number of disease organisms in the water and provide a cleaner environment for the fish to recover in. It also removes a lot of the gunk and this means any medication can work on treating the fish instead of being wasted killing the pathogens in the gunk.
Make sure any new water is free of chlorine/ chloramine before it is added to the tank.
Clean the filter if it hasn't been done in the last 2 weeks. However, if the filter is less than 6 weeks old, do not clean it. Wash the filter materials/ media in a bucket of tank water and re-use the media. Tip the bucket of dirty water on the garden/ lawn. Cleaning the filter means less gunk and cleaner water with fewer pathogens so any medication (if needed) will work more effectively on the fish.
Increase surface turbulence/ aeration to maximise the dissolved oxygen in the water.
Add some salt, (see directions below).
-------------------
SALT
You can add rock salt (often sold as aquarium salt), swimming pool salt, or any non iodised salt (sodium chloride) to the aquarium at the dose rate of 1 heaped tablespoon per 20 litres of water. If there is no improvement after 48 hours you can double that dose rate so there is 2 heaped tablespoons of salt per 20 litres.
Keep the salt level like this for at least 2 weeks but no longer than 4 weeks otherwise kidney damage can occur. Kidney damage is more likely to occur in fish from soft water (tetras, Corydoras, angelfish, Bettas & gouramis, loaches) that are exposed to high levels of salt for an extended period of time, and is not an issue with livebearers, rainbowfish or other salt tolerant species.
The salt will not affect the beneficial filter bacteria, fish, plants, shrimp or snails.
After you use salt and the fish have recovered, you do a 10% water change each day for a week using only fresh water that has been dechlorinated. Then do a 20% water change each day for a week. Then you can do bigger water changes after that. This dilutes the salt out of the tank slowly so it doesn't harm the fish.
If you do water changes while using salt, you need to treat the new water with salt before adding it to the tank. This will keep the salt level stable in the tank and minimise stress on the fish.
When you first add salt, add the salt to a small bucket of tank water and dissolve the salt. Then slowly pour the salt water into the tank near the filter outlet. Add the salt over a couple of minutes.
If there's no improvement after 2 days with salt, post more pictures and test the water quality again.
The white mark is excess mucous covering a fairly large wound. The fish is also covered in excess mucous, which suggests something is not right with the water quality.
-------------------
Check the ammonia, nitrite, nitrate and pH of the water. Then do the following.
Wipe the inside of the glass down with a clean fish sponge. This removes the biofilm on the glass and the biofilm will contain lots of harmful bacteria, fungus, protozoans and various other microscopic life forms.
Do a 75% water change and gravel clean the substrate. The water change and gravel cleaning will reduce the number of disease organisms in the water and provide a cleaner environment for the fish to recover in. It also removes a lot of the gunk and this means any medication can work on treating the fish instead of being wasted killing the pathogens in the gunk.
Make sure any new water is free of chlorine/ chloramine before it is added to the tank.
Clean the filter if it hasn't been done in the last 2 weeks. However, if the filter is less than 6 weeks old, do not clean it. Wash the filter materials/ media in a bucket of tank water and re-use the media. Tip the bucket of dirty water on the garden/ lawn. Cleaning the filter means less gunk and cleaner water with fewer pathogens so any medication (if needed) will work more effectively on the fish.
Increase surface turbulence/ aeration to maximise the dissolved oxygen in the water.
Add some salt, (see directions below).
-------------------
SALT
You can add rock salt (often sold as aquarium salt), swimming pool salt, or any non iodised salt (sodium chloride) to the aquarium at the dose rate of 1 heaped tablespoon per 20 litres of water. If there is no improvement after 48 hours you can double that dose rate so there is 2 heaped tablespoons of salt per 20 litres.
Keep the salt level like this for at least 2 weeks but no longer than 4 weeks otherwise kidney damage can occur. Kidney damage is more likely to occur in fish from soft water (tetras, Corydoras, angelfish, Bettas & gouramis, loaches) that are exposed to high levels of salt for an extended period of time, and is not an issue with livebearers, rainbowfish or other salt tolerant species.
The salt will not affect the beneficial filter bacteria, fish, plants, shrimp or snails.
After you use salt and the fish have recovered, you do a 10% water change each day for a week using only fresh water that has been dechlorinated. Then do a 20% water change each day for a week. Then you can do bigger water changes after that. This dilutes the salt out of the tank slowly so it doesn't harm the fish.
If you do water changes while using salt, you need to treat the new water with salt before adding it to the tank. This will keep the salt level stable in the tank and minimise stress on the fish.
When you first add salt, add the salt to a small bucket of tank water and dissolve the salt. Then slowly pour the salt water into the tank near the filter outlet. Add the salt over a couple of minutes.
If there's no improvement after 2 days with salt, post more pictures and test the water quality again.
