What's new

Moldy Betta


New Member
Apr 11, 2019
Reaction score
I purchased a veil tail female today. When I got her I noticed her fins were a bit clamped( at least that’s what I thought. I’m not for sure that’s what it is) however there was nothing else that caught my eye as alarming. I took her home to place her into my heated/planted/cycled 10 gallon.

However, I rearranged the 10 gallon before putting my new fish in it. I noticed she was looking significantly more clamped than she had an hour ago. Also, there appears to be a moldy like substance growing along her body and her all over her face. None of this ‘mold’ was present a few hours before when I bought her.

What could be wrong with her and how could I treat it. I was looking forward to putting her into my tank!

I also attached some images but given she kept moving and how dark she is my camera had difficulty focusing and catching the moldy..



Jan 26, 2008
Reaction score
Perth, WA
I can't see much on the face, another picture might help.

If there is a cream or white film rapidly appearing on the face, it is excess mucous caused by something in the water that is stressing the fish. Fish have a thin layer of mucous over their body and when they are stressed by parasites or something bad in the water, they produce more mucous that appears as a cream, white or grey film on them.

Clamped fins are usually caused by poor water quality that allows bacteria and protozoans to infect the fish.

How long has the tank been set up for?
What are the tank dimensions (length x width x height)?
How often do you do water changes and how much do you change?
Do you gravel clean the substrate when you do a water change?

What is the ammonia, nitrite, nitrate and pH levels in the tank?
If you don't have test kits, take a glass full of tank water to the local pet shop and ask them to test it for you. Write the results (in numbers) down when they do the tests and post the results here. If the shop says the water is fine, ask them for numbers.

What sort of filter do you have?
How often and how do you clean the filter?

What other fish are in the tank?
Have you added anything new to the tank in the last 2 weeks?

Do a 75% water change and gravel clean the substrate every day for the next 2 weeks or until the problem is identified or resolved. Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

Make sure any buckets you use for the fish are clean and free of chemicals, soaps, cleaning products, grease, oil or anything else. If possible, buy a couple of buckets and use a permanent marker to write "FISH ONLY" on them. Use those buckets for the fish only and nothing else.

Make sure you don't have any creams, grease, soaps, oils, perfumes, deodorants, paints, residue from anti-bacterial soaps on your hands when feeding the fish or working in the tank.

Back in the fold

Fish Herder
May 25, 2019
Reaction score
Billings Montana USA
Colin gave the best advice ever in his post and you don't hear it repeated often enough. Have clean hands with no soap residue on them when you're working in your water and have fish only buckets for your water. This is basic information and, again, it isn't repeated as often as it should be. Learn it, know it, live it.