I have my 30g on a walmart stand that was meant for a 55g. Thought it was the same. But it different. It quite nice for a walmart item.
When I went to pick up the box, It was heavy, i knew it wasnt cheap particle board.
Particle board is heavier than solid wood.
Only thing I would worry about is your doors. With a miter you are gluing mostly edge grain. Not much strength there. You also glued your panel in from what I can tell. Down side to that is as the panel shrink and evpands it wants to rip apart the miter. Most doors are stub tenons on the stiles into the rails.