Re: False bottom vs Hydro
I prefer Matala for its very light weight, and its lovely ease of cutting & shaping.
I've used LECA ("hydro balls") plenty in drainage layers, and am still working through a 40-L bag I got on sale from a local hydroponics shop. But mostly now I just use the LECA in DIY substrate mixes.
One good thing about the LECA, you can wash and re-use it "forever". Even bake it in the oven. You can bleach Matala, but I wouldn't bake it! Ha ha ha.
Anyway - good luck OP!