What is wrong with just getting a small predetory fish for the 30 gallon... or buy a 55 gallon set that usually go on sale... some of the smaller cichlids have just as much personality as the large glass bangers you see in videos and are much easier to care for... like EBA or keyholes... or dwarf cichlids/pike... after a year with that if all goes well (hopefully) you'll realise the difficulty in keeping fish and how much it costs for dechlorinator/food/meds(salt)/plants....new heaters! And you'll have some experience to move up