Some goby species live in symbiosis with burrowing shrimps and needs to traverse areas of semi dry land. So keeping the dry sand instead of gravel would be better place for gobies to live and also use a set of gobies with its own varieties to support a companion. Also look out for low watt bulbs for aqua tanks. You can find more helpful resource links from here:
Aqueon Deluxe 20 Gallon Aquarium Kit

Goby Fish

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