For a softie tank, I went with coral skeleton/shells as substrate. This is so I can just toss stuff to stick where they please. Like a giant mushroom box.
With no fish, pest control has been a problem. Most algae is non existent since I seeded with pods and have a few snails. I have some bubble but not too bad. However, so many flatworms....Bad pic but all those dots on the glass are worms.
I want to do seahorses in here and lower temp like 75 so I'm not sure if there are any options for fish docile enough to not upset the tank. There are enough pods for a scooter so I'll probably add one of those.