after the upgrade, improved storage tanks stopped taking any liquids

Sorry to hear that.
Does it have any liquid at all? (Stay empty or stay at some constant level?)
What kind (and tier) of pipe/pump is it connected to?

I have an old game, a lot of improved tanks of the maximum level. Connections with and without pumps, fluid comes out normally. But he refuses to enter. Not with or without a pump.
pumps and pipes are conventional.
The tanks are not empty. But not complete either.
It looks like a level 7 tank, now it takes a maximum of 100 thousand liquid, although it owes 400 million.
I played yesterday, everything was fine. The problem is in the update. The bug is critical, it is impossible to continue the game.

Guess you do not apply pumps into storage tanks, and using higher tier of storage tanks than other entities (pipes, pumps, oil refinery, etc.).
I have unintentionally also applied "pressurized fluid box" to storage tanks during code refactoring.

In former versions, storage tanks are in "normal pressure". So its pressure is lower than most machines. This means pumps are not needed for inflow into storage tanks; but need immediate pumps for outflow (except the tanks are outputting to machines directly, i.e., no pipes in between).
In code refactoring 0.17.11 / 0.18.2, I have unintentionally changed the storage tanks into "high pressure" mode. Its pressure is the same level as same-tier pump (or other output from chemical plant, oil refinery). It requires an inflow same-tier pump to fill a tank fully; but do not need any outflow pumps.

I will release an update in an hour or two, to revert back this change.
Also I feel the former "normal pressure" storage mode will be more practical, in terms of gameplay purpose. (In reality, however, the only option for gases is to be stored in compressed form.)

Thank!
I'm really looking forward to the whole chemical industry has stopped.
The old version was really better.

Just uploaded 0.17.12 / 0.18.3.
Tell me if they are not working for you.

All ok!
thx!