ontstudios a 10mb quota is very low and is going to be an issue for most database-connected software (which is common for forums, blogs, etc). It seems like the hosting you're using is not very friendly to these applications in general, really. If you can look for better hosts that don't restrict MySQL database sizes, you'll have an easier time working with Flarum or other database-using software.
If you can't find other hosts for some reason, then you might need to consider a solution other than Flarum, I'm sad to say. SMF (with a configuration option) and some perl/CGI-based forums use flat-file forms, or you can look for a forum that uses sqlite as well.