Project for small underwater pressure and temperature sensing feasible?

Hi all, I'm new to Arduino, but it seemed like the best platform for something I'm looking to do, and I was wondering if what I'm looking to do is feasible (and simple for a newbie to put together / code) on the platform. So, I want to create a device that's waterproof (I have a casing already), as small as possible, and can sense the pressure and temperature underwater. This device need not a display but rather would transmit a Bluetooth signal with the water pressure and temperature for processing / display on a different device. I'm also looking to keep size and cost down, and I've found these parts (I plan to use the Arduino Nano 33 BLE):

Thank you for your help!

Is the pressure that is small, or the enclosure?

Thanks for your reply. I'm trying to minimize the size of the enclosure, but I'd rather have function over form. The maximum pressure needed to be measured will be 6 bar.

To the OP: Bluetooth isn't going to work well underwater.

My goal is to have the device able to transmit data a few feet underwater to a separate display / storage device. Would that be feasible?

How many feet is "a few feet"?

~6 at most.

It will fail.

At what rate?

I'm not sure I follow what you mean by "rate". I just want to be able to have the temperature (in Fahrenheit, go America) and pressure in bar (preferably up to the hundredths position) be able to be transmitted via Bluetooth, updating at a minimum of one time per second.

Oof. What's the highest range I can get?

Or would WiFi work better?

Number of readings per unit time.

Wifi uses the same RF frequency as BT, 2.4GHz. The rate of signal absorption in H2O is extremely high.

About as badly

The higher the frequency, the less the range. WIFI, likely a few inches.

Idk much about signaling but would WiFi on the 5Ghz band work better?

See reply #15

At least one time per second (each 'update' can consist of one sensor, so each sensor needs to update once every two seconds.

EDIT: The device will be used in open water, so I think it'll be hard to use a tape measure there.

So if Bluetooth or WiFi won't work, then is there any other way to do it?

Why not a wire?

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