Algae...
Feeding the tank, small skimmer and other organic nutrients play with algae problems too.
To remove by hand/ tweezers is not the way to go. That only gives us some room to play with the real toys!
1) Make sure the evaporated water is replaced with RO/ DI/ Carbon filtration.
2) Water changes using also filtered water with a good salt.
3) If natural salt water is used for water changes you need to keep an eye on the tank and try the synthetic to compare. Not all the natural sea water is good and low in nutrients.
4) Try not to overfeed the tank at all costs. But feed the animals!!! Find the balance.
5) Make sure your lights are ok for the size f your tank.
6) Temp around 79F is a good way to avoid too many algae.
7) Make sure you skimmer is the right size for your tank.
8) The use of kalkwasser is great to help water chemistry against algae.
8) The use of carbon in the tank will help too.
9) Keep natural predators (fishes and snails) to help.
These are the 10 golden tips against algae problems.
The use of UV light and Ozone are not necessary, but options of some.
Now you need to search about the use/application of all the methods above...
Have fun!
Grandis.