Broken back disease?

[Patrick1104]

I currently have 3 zebra danios in my 5.5 gallon tank. Over the last two or three weeks, I started noticing curved spines on two of them. Could this be caused by poor water condition, vitamin deficiency, or other problems? Is there anything that could be done to help them?

https://imgur.com/a/uNFz6XD

Thanks.

 

[Autumnsky]

It can be caused by internal parasites or vitamin deficiency usually. Vitamin C is often needed

Click the nutrition box for details
https://www.hikariusa.com/marine_folder/seaweed_extreme.html
has ascorbic acid which is a form of vitamin C

You can check other foods in case you already have some kinds of food with ascorbic acid or vitamin C

Some of the treatments could damage biological bacteria and or snails /shrimp.
You can check on Seachem Paraguard or Prazipro
https://www.seachem.com/paraguard.php
PraziPro - Hikari Sales USA