Leaderboard

You have to downgrade

Is the server hosted on your PC? Are you trying to have your brother join via the same IP as your friends? If you answered "yes" to both of those questions, you may be entitled to compensa- I mean... that's not how someone on your network should connect to the server, you'll need to have your brother connect using your local IP rather than your external IP.

Regarding "unnecessary lag": if the sole reason for a tile entity is for rendering, your TE does not need to tick and thus won't produce any lag. Technically, the presence of any tile entities in a chunk mean a little more work to load the chunk, but if you have enough instances of your TE in a chunk to cause loading performance issues, then you probably also have enough to murder client performance with all the rendering that's going on. tl;dr non-ticking tile entities produce zero lag unless you grossly abuse the feature.