Some aquarium decorations open and close, move up and down, or otherwise move. If you choose one of these items, be aware that your fish may be attracted to the bubbles that they produce. If your fish swims into contact with one of these moving decorations it is possible that it might become injured or trapped.
Provide your fish with enough hiding places to make it feel comfortable in its environment. Be certain that any hiding places are large enough for your fish to easily enter and exit from at its adult size. Some fish prefer plants to hide in; consider buying a plant light to keep them healthy.