you have superior vision in dark and dim Conditions. You can see in dim light within 60 feet of you as if it were bright light, and in Darkness as if it were dim light. You can’t discern color in Darkness, only Shades of Gray.

As a goldfish exposure to open air dries your gills and causes you to suffocate.

As a goldfish your body is coated in a thin layer of mucous which makes it difficult to grasp without the aid of claws or fangs.

Through currently unknown means you are able to control and shape up to 50 gallons of water (Or 7 cubic feet). This does not require concentration. as an action you may move the mass of water up to half your remaining swim speed, you are not limited on how much of the mass you move at one time, but are unable to move it into an occupied area. The water must be in liquid form and of a safe temperature range, lest you take the following penalties:

Hot water: While traveling through water that has been heated beyond 120 degrees (F) you suffer 1d6 fire damage for every 5 feet traveled.

Cold water: Water that is below 40 degrees (F) costs double movement and disadvantage on Rolls to dexterity, and attack rolls.

Through necessity you have learned to cast Create or Destroy water.

This does not count against your available spell slots and may be cast 3 times at 1st level OR 2 times at 2nd level OR 1 time at 3rd level.

If you have already cast this spell at 1st level you may cast it once more at second level.

The ability to use this spell refreshes after a long rest.

Being a fish gives you access to speech of water creatures (Primordial aquan along with base understanding of the tongues of non-aquatic primordial speakers)

Through your travels you have learned the common tongue and one other language in addition to Primordial.