buy a book on saltwater tanks and read it. Don't expect to learn everything from a few questions in a forum.
if you google "batfish" you could learn everything about them, and if you had some questions then you could make a post here.
it took me 30 seconds to copy and paste this about bat fish
Batfish Aquarium Care
In my experience there are two general reactions when people see a batfish: 1) “That’s the ugliest thing I’ve ever seen.” or 2) “That’s the coolest/cutest thing I’ve ever seen.” With a growing interest in the ornamental aquarium trade for unusual specimens, batfishes may seem to be the perfect fish for those interested in the rare and unusual. However, batfishes are not for everyone as they require specialized care to survive in captivity. The information listed is based solely on my experiences with these fishes. As such, they are my own, may differ from those of others, and by no means are the definitive conclusions of their captive care or biology. However I will state here that I am not liable for any losses, injury, or problems that may occur from your use of this website or the information provided by it. I do welcome any comments or experiences by others as this can only further our understanding of these unique fishes.
Species Encountered in the Trade
In the aquarium trade, only three species of batfish (Ogcocephalus cubifrons, O. nasutus, and O. vespertilio) are likely to be encountered. The first (O. cubifrons) is the most common species in the shallow waters around Florida and the one most commonly taken by trawlers on both sides of Florida’s Coast. It is the species most likely to be encountered in the aquarium trade. O. nasutus is the species that usually arrives in shipments from the Caribbean such as Haiti. The long-nosed batfish arriving in shipments from Brazil is O. vespertilio. It is often mistakenly identified as O. corniger. In addition, I have come across a handful of Halieutaea indica over the course of several years, which were sold to me as pancake batfish, from a saltwater fish wholesaler in Los Angeles.
Aquarium Setup
For starters, these fishes come from habitats with large open areas and very little structure. An aquarium for a batfish should emphasize length/width rather than height. The size of the aquarium needed to house a batfish depends on the species and adult size of the fish. I have found 30 (30"L x 18"W x 12"H) or 40 gallon (36”L x 18”W x 12”H) “breeder” aquariums and 20 (30"L x 12"W x 12"H) or 33 (48"L x 12"W x 12"H) "long" aquariums to be excellent for smaller batfish specimens (e.g. pancake batfish or Ogcocephalus batfish less than 5 inches). For larger specimens of Ogcocephalus batfishes I used tanks ranging from 75 – 120 gallons.
A batfish tank should always be covered and if large individuals are kept, a weighted cover should be used. I have had specimens ranging from small pancake batfish to foot long Ogcocephalus cubifrons jump out of uncovered or lightly covered aquariums or holding tanks. Batfishes are reportedly nocturnal (Combs 1973, Winans 1975, Gibran and Castro 1999, pers. obs.) however I have found that they will readily acclimate to a normal day/night aquarium light cycle under a standard fluorescent bulb. LED “moonlights” may be used to view a batfish at night or to ensure a newly acquired batfish is acclimating properly in an aquarium.
