You are able to see by means of the water in the air up to 60ft away in humid areas, 15 feet away in dry areas, and as far as possible underwater.

Creatures that have no water in their bodies are invisible to you while in areas with dry air.

Writing becomes invisible to you once it is dry.

You are otherwise blind.

You do not need to eat, sleep, or breathe, but getting water is still necessary for you. To gain the benefits of rest you only need to take the time to meditate.

You are immune to sleeping effects.

You do not need to squeeze to get through a gap that is a size smaller than you and you can get through any size gap that is smaller by treating it as difficult terrain.

You do not age and are immune to aging effects.

You do not have a constitution score and are immune to most constitution saves. The exceptions are: constitutions saves to resist the damage from extreme temperatures, which you will automatically fail (as you do not have a way to control the temperature of your body) and saves to resist damage (which will be replaced with strength saves). 

Your strength is what holds you together. Because of this, Your HP is affected by your strength bonus instead of constitution.

You can share your space with any number of other creatures.

You can change your body into any shape freely.

You can speak, write and read Aquan, and you may choose two other languages to understand, but you will not be able to speak verbally with any languages other than Aquan and Primordial.

Your body is a fluid making you immune to the grappled condition.

Your wet body causes you to have disadvantage on climb checks, grapple checks and on holding onto things in general.

You have a -2 to ac while wearing armor due to the need hold the armor steady while your body naturally shifts and sways.

You have a -1 penalty to attacks and damage when using weapons that are not natural weapons.

Immunity to poison, the poisoned condition, thunder damage, disease, sleep effects, exhaustion, deafness, blindness, and catching on fire.

You have resistance to lightning damage and if you take lightning damage while in contact with another creature you share half that damage with them.

You have vulnerability to bludgeoning damage.

You are extremely vulnerable to cold damage taking 4 times as much damage as you normally would in negative temporary hit points.

However, damage from cold is always considered to be non-lethal (it will only ever bring you to 0 hp, no less, it will never kill you, but you will gain the paralyzed condition) and the damage from it falls off by 1 point of damage per round (unless you are a frozen area). 

When taking cold damage you must succeed a strength saving throw with a DC equal to the damage you've taken.

Taking cold damage will slow you by 5 feet for every 5 damage that you take from it (this reduction falls off by 5 feet every time 5 points of cold damage falls off).

Fire damage will remove the cold damage you've taken by the same amount of fire damage you've taken (if you are at zero hp when you take fire damage the damage will still be considered lethal and you will die).

If you hit 0 hp you will die instantly not getting any death saving throws (the only exception is when you hit 0 hp from taking cold damage).

All damage that can harm you is considered lethal except for cold damage.

You have advantage on stealth checks to appear as a puddle if you are not carrying any items or equipment.

You may auto-grapple creatures that are smaller than you when you move into or through their space. At the beginning of their turn, they may make either an athletics or acrobatics check against your athletics (at disadvantage) to free themselves from the grapple. On a failed attempt you can choose to deal 1d4 points of force damage to them.

As an action, if you are in contact with enough water, you may make a DC 5 Strength saving throw to grow to the large size category, a DC 10 Strength saving throw to grow to the huge size category, a DC 15 saving throw to grow to the gargantuan size category, or a DC 20 to grow to the colossal size category.

On each of your following turns, you must take an action to maintain the size you chose with the same DC as before or you will return to medium size, releasing all the extra water you were holding on to.

Increasing in size category this way does not increase your stats or damage.

You are immune to healing effects including healing from hit dice from short rests or from long rests.

The only healing that you can receive is from taking an action while in contact with a liquid for you to absorb the water from the liquid you are in contact with, allowing you to heal by 1d4 + your Wisdom modifier.

Acid is the only liquid that you cannot heal from.