So as on vid...
https://www.youtube.com/watch?v=qVo6jHovRAw
While pumps stay - water level is just epic falling to almost 0.1 while BEFORE pumps it has 10.0 (on video clearly seen when i come to water pumps). After removing them - liquid just instantly fill water tank.
At the end we tried to place line of pumps so only after that water filled the tubes. But i left to post bug after end video, previously pumps worked even like few days and then suddenly stop work too, so even this decision could not be right i think.
My thoughts:
We was very low electricity every night so maybe some pumps was like saving low level of electricity and continues slow working even after electricity was back to high level again
Sometimes it helps when i just rotate them to 180degree and back
Also sometimes it helps me to run them when i place them on builded tube
Small pumps completely bottleneck/block liquid [14.21]
Re: Small pumps completely bottleneck/block liquid [14.21]
Pumps pump slower than the offshore pump outputs. That's not a bug. It's poor design and we changed it for 0.15 but it's working correctly for what they were programmed to do in 0.14 
If you want to get ahold of me I'm almost always on Discord.