Nuvo 20 good for seahorses?

Hello I’ve had a 20 gallon nuvo set up for about 6 months now with plenty of macros gorgonians and sponges. I was wondering if this tank was too short to keep seahorses. I’ve kept seahorses in this tank before but then they died and I was looking into getting another pair. The nuvo 20 is 13 inches and I read on this forum that tanks should be tall or else it could kill the ponies. Do you think this tank is tall enough to keep a pair of erectus? If not what should I loook into getting?