Spot on Black Molly

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Fish Crazy
Feb 14, 2024
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Picture follows.

This white spot, looks like a bubble, appeared overnight, it was not present when we put the fish to bed last night.

No other fish are afflicted at this time.

37 gallon tank
WC 30 percent each four days
Am 0 —- No 0 —— Na 10 —- PH 244 —- KH 120 —- PH 7.5 —- water temp 75F

It's hard to see clearly. It looks too large for Ich, but I can't see if I'd suspect bacterial or fungal, from a wound. How long have you had the fish, and what are the water hardness, and temperature?
Hardness 244 and temp is 75F. He is an original so Feb this year.

He and the male gold lyretail do get rambunctious at times. The gold is a bit larger and used to back off but no longer does. It is not constant action but it does occur. Up close it gelonous. Not spelled right but you get the idea.

The photos are too blurred to make a real determination of the problem. The way I see if from the blurred photos, that it looks like fungus. But again, a more clear photo would tell us more...
The photos are too blurred to make a real determination of the problem. The way I see if from the blurred photos, that it looks like fungus. But again, a more clear photo would tell us more...
I will try for a better photo. He refuses to pose so far.
Salt is better than pimafix, melafix or bettafix.

Using Salt to Treat Fish Health Issues.

For some fish diseases you can use salt (sodium chloride) to treat the ailment rather than using a chemical based medication. Salt is relatively safe and is regularly used in the aquaculture industry to treat food fish for diseases. Salt has been successfully used to treat minor fungal and bacterial infections, as well as a number of external protozoan infections. Salt alone will not treat whitespot (Ichthyophthirius) or Velvet (Oodinium) but will treat most other types of external protozoan infections in freshwater fishes. Salt can treat early stages of hole in the head disease caused by Hexamita but it needs to be done in conjunction with cleaning up the tank. Salt can also be used to treat anchor worm (Lernaea), fish lice (Argulus), gill flukes (Dactylogyrus), skin flukes (Gyrodactylus), Epistylis, Microsporidian and Spironucleus infections.

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 (5 gallons) 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 1 to 2 weeks.

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 (2 litre) 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.
Thank You for the suggestion, Collin T. I have a BN Pleco in this tank I think I read somewhere salt is not advised. I may remember wrong as I have read somuch information my memory is sometimes a jumble, or is that jungle.

At any rate, this morning the white spot seems to be reduced, maybe my imagination. I am thinking it may be a wound and perhaps it would be best to observe the Molly for another day or two to see what progresses. I am also considering a 10- or 15-gallon tank purchase for use as a hospital and QT tank. I have felt no need for one because I have no plan for additional fish purchases until late fall, we have plenty of Molly, Guppy, and soon Endler juveniles to select from if we need, (want) to increase population. Currently no plans to do so. A hospital tank might make sense though and we have plenty of seeded filters that can help cycle it quickly.
Bristlenose catfish are fine with the dose rate of salt in post #9
Agreed. You'll read in a lot of places that catfish can't tolerate a little temporary salt. It's a myth.
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We decided to follow Colin T’s advice and instructions and are starting the salt bath as soon as Linda returns with proper salt.

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