Float-tanks are this:

Imagine a bigger-than-normal bathtub, so you can sprawl-out ( arms & lega akimbo ) without hitting the sides..

the water-density is upped with brine, instead of plain water ( the float-tanks place I used to go to used sacks of "bitter salts" & the texture of the brine was damn-near oily, and DO NOT EVER shave shortly before going into a brine-soak, or you're going to discover what stinging really means )

also it is brought up to a person's body-temperature, or close to it.

When there's no temperature-difference, & you're floating sooo high that drowning is much less likely ( the Dead Sea is probably the prototype for all float-tanks, btw ), & you aren't bumping into the walls, then you're in blissful sensory-deprivation ( total dark, too, obviously, probably use a timer, limit it to 2h max ), & meditation can be awesome in these conditions.

_ /\ _

You can do it on your floor if you take enough ketamine.

In all serious though, not really. I think other people already pointed out why.

However you can also learn to close the sense gates, without drugs or a bathtub. Later Jhana meditations do this.

And even just you relaxing in your bathtub with your ears under the water, that's a step towards that stuff. The whole idea is to get very relaxed and minimize the stimulation from your senses, so that your mind can just relax and drift and be.

It doesn't need to be full sensory deprivation to get the benefits in other words.

Are you asking this because of Stranger Things?

I think the biggest issue is that a bathtub isn't big enough for most people to float in without touching the sides. Assuming the tub is large enough, the epsom salt would work to make you float and would be cost effective. You would have to figure out a way to regulate the temperature to 98.6 degrees though. And you would have to be in a pitch dark room.

It's not practical.

However, have a shower in the pitch dark sometime. It's the most ridiculously soothing thing imaginable.

Put your shower gel and stuff where you can find it by feel, obvs.

The float place near me uses something like 1200 pounds of Epsom salt in a tank that is maybe twice the volume of my bathtub. Then they also regulate the temperature within the tank, both air and water, to be close to normal skin temperature. I'm not sure it's practical.

I think your best bet is probably some kind of kiddy pool/pet bath with sufficient depth. Even most jacuzzi style tubs aren't actually big enough for an adult to float in.

Would take a lot of salt though.

Not my bathtub, no. It's too small.