I am brand new to saltwater. My son got an 8 gallon bio cube. I know this is too small, but I promised I'd try. I have 1 piece of dead coral for decor and that's it. We hope to have 2 tiny fish and maybe 2 shrimp. We also like hermit crabs. What equipment, substrate would you guys suggest? I'd like to use easy (forgiving) live macro algae to help balance this tank. Please be kind with responses. I have been called names elsewhere and was referred here to learn.