Tanning tubs bugged?

[Cerise]

I have 4 limed hides in a tanning tub filled with 5 % solution of tanning liquid. The meter shows it at 61 percent filled however there are no indicators showing any tanning progress? It is not the first time I have made leather but it is the first time I have encountered this. Thanks in advance for any input.

[MagicManICT]

The timers should show up as pie wedges on each hide in the tub. I believe it takes 8 hours for the hides to tan. As long as you have 10L of fluid per hide at the 5% solution, you should be good.

[Kandarim]

just to be sure, you can always toss an extra brain in there. It might be the fact that the concentration is rounded up towards 5% (I had this problem after using a second-hand tub).

To be tanning: the graphics of the tanning tub must show water (which means the concentrations is high enough & there is at least 10L of tanning fluid in there) and hides (which means there are hides to be tanned).

[Cerise]

I added another brain as you suggested and the liquid became visible again so it must have been rounded up, thanks for the advice!