not necessarily... this assumes that your return flow > than the flow rate of your skimmer pump:
1) find a tall, open-topped box (plastic / glass) that is taller than the current water level in your sump & that will fit in the return section of your sump
2) place it beneath the return floe from the tank. At this point the 'box' should fill up and overflow into the sump - key feature is that the level of water in this 'box' will not change, it will always be exactly the same = overflowing.
3) place the pump (or entire skimmer) in this new box.
That's it - constant water level.
you just need to find / make the right box.
Does it all make sense?
If you don't find a solution like this, you will be condemned to a life of eternal skimmer tuning :grumble: I was there, because I was told the SS was not affected by water level when I bought it, so placed in an area of the sump that fluctuated with evaporation... hmm - you know another solution would be an auto-topoff system to keep you sump level constant..... anyway I moved it & life improved!