Just got done investigating a spambot we had earlier, and it looks like they used a lot of compromised accounts on other instances to give their post an initial upvote boost. If you don't already, please remember to use a good strong password. Keeping your account secure helps reduce spam across the whole of lemmy, and keeps your account from getting banned for things you didn't actually do.
I recommend Diceware! I use it in my professional capacity as an IT/Security person, and also you get to use your mathrocks!
EDIT: Oh, also, all that numbers and symbols shit is no longer considered good practice. Just make it a really long collection of random words, at least 12, ideally 16+ characters. And make sure the words are actually random; your 3 favorite sports teams isn't good enough, which is why I recommend diceware.
30 characters? you don't need that, we only let you use up to 10. also yes you have to have at least one lowercase letter, uppercase letter, number and a symbol (which can only be !, @, #, or $). we're doing this for your security, of course