Welcome aboard Nathan and Kobus.
Nathan, is that really 150L?? "Being BIAB for 3 years or more with 150L system,"
If so, you can teach us lots of things. like, How does one lift that bag? Otherwise, we can still learn from one another at just about any time. Ask questions and post something new that you find interesting.
Kobus, there is lots of good information for you on this forum. The excel spreadsheet called BIABacus, https://biabrewer.info/viewtopic.php?f=5&t=1869
can be used in Libre Office (remember to save the file with .xls at the end of the filename). It will eventually help you see how everything works together in building a recipe.
will help you get familiar with terminology used here for clear communications.