White Covering on Fish

[denogginizer]

(I am not including water parameters yet, as I just finished a 75% plus water change, but I can add them later.)

This tank is about 30 gallons and has been up and running well for about two years.
It currently holds 6 Celestial Pearl Danios, 4 Cory Cats and a few Mystery Snails.

The Danios have a white covering on them. At first, I thought it was Ich, but now I am not sure.

Please see attached pic and video.
Thanks!

Video Link:

https://imgur.com/0Sg0pWR

or

https://imgur.com/a/OgyBrUo

 

[AdoraBelle Dearheart]

Oh no, I'm worried it might be columnaris... also called 'saddleback disease' because it can show as those distinctive 'saddle' patches @Colin_T?

Have you added anything new to the tank recently?

 

[HoldenOn]

Could also be excess mucous.

 

[denogginizer]

Oh no, I'm worried it might be columnaris... also called 'saddleback disease' because it can show as those distinctive 'saddle' patches @Colin_T?

Have you added anything new to the tank recently?

I have never heard of that disease. Thanks for the information. I have not added anything recently.

 

[AdoraBelle Dearheart]

I have never heard of that disease. Thanks for the information. I have not added anything recently.

When was the last time you added something? Not even any new plants or anything?

How many fish are showing the white patch, and do they all look like that saddle shape on the back?

 

[denogginizer]

When was the last time you added something? Not even any new plants or anything?

How many fish are showing the white patch, and do they all look like that saddle shape on the back?

Three of the six Danios show white on them. It's not just a "saddle shape". A couple of them are basically covered in it.

I might have added some plants from my overgrown 75 gallon tank (that does not show any disease) about a month ago or so.

 

[AilyNC]

They're quite a shy fish. Do you've any floating plants for shade? And many hiding spots?

 

[denogginizer]

They're quite a shy fish. Do you've any floating plants for shade? And many hiding spots?

The tank had a lot of plants in it, but I removed a bunch while I'm trying to figure out what is going on. Just trying to keep everything as clean as possible right now.
When I get the disease figured out, I can move plants from another tank, back into this one.

 

[itiwhetu]

ammonia level. pH please.

 

[Colin_T]

Check your water quality for ammonia, nitrite, nitrate, pH and GH.

Do a 75% water change and gravel clean the substrate.
Make sure new water is free of chlorine/ chloramine before it's added to the tank.

Clean filter if it hasn't been done in the last 2 weeks.

Post clear pictures (not gifs or video) of the other fish.

--------------------
It looks like excess mucous, which is normally caused by poor water quality, a dirty tank, chemicals in the water, or an external protozoan infection.

 

[denogginizer]

ammonia level. pH please.

PH = 7.4 to 7.5
AMM = 0

 

[itiwhetu]

That is at their limit for pH. They will be happier closer to 7.0. And lots of plant.

 

[denogginizer]

Check your water quality for ammonia, nitrite, nitrate, pH and GH.

Do a 75% water change and gravel clean the substrate.
Make sure new water is free of chlorine/ chloramine before it's added to the tank.

Clean filter if it hasn't been done in the last 2 weeks.

Post clear pictures (not gifs or video) of the other fish.

--------------------
It looks like excess mucous, which is normally caused by poor water quality, a dirty tank, chemicals in the water, or an external protozoan infection.

Ammonia: 0
Nitrite: 0
Nitrate: Maybe 2-3
PH: 7.4 to 7.5

Did a 75% plus change yesterday

Squeezed out the filter in tank water about two weeks ago. Will do it again.

Thank you for the help. If it's excess mucous, will that take care of itself with better water quality?

 

[HoldenOn]

Excess mucous is from stress. Can we get a full tank picture and a list of tank mates?

 

[Colin_T]

The water seems fine and the clamped fin with white layer over the fish's back would suggest an external protozoan infection like Costia, Chilodonella or Trichodina.

Add 2 heaped tablespoons of rock salt for every 20 litres of water. Keep salt in there for 2-4 weeks. If there's no improvement after a couple of days with salt, you might need a chemical medication to treat external protozoan infections. But try salt first.