Memory Limit Reached Error

I’m noticing (and heard from other visitors) that an error message will come up randomly during browsing of my site. See shot here:

https://www.dropbox.com/s/3sdx1o66fwagwl5/bw-mem-ex.png

It’s a memory limit reached error. I asked my host, siteground, where I have a cloud vps account, and they upped my memory and said it doesn’t look like it’s caused by traffic as I don’t get a ton. So maybe it’s a plugin causing it.

Is there are any case where the security plugin throws this error mistakenly? I find it hard to believe that a plugin somewhere on the sites I host on this vps are using up so much memory that it stops loading the page and gives an error.

Thanks for any insight you can provide!

https://www.ads-software.com/plugins/better-wp-security/