Keeping gars. Hujeta, and needle nosed
The first gars I've had are the "Hydro" gar or Hujeta (sp?). I've seen them along with the needle nosed gars most frequently in aquarium stores. The Hujeta Hydro gar is a silver colored fish with "glenoid" or diamond shaped scales, a black spot on it's tail, and a protruding snout typical of the gar species. The Needle Nosed gar has a very long snout with a dark stripe all the way down it's body and less prominent glenoid scales.
The Hujeta and the Needle Nosed gar should be kept in groups of at least 2 and it's said that 2 males with 1 female is ideal. Sexing is difficult however, but the females grow faster and bigger than the males, so if given a selection from the same batch I would take 1 larger and 2 smaller. These fish like each others company and look good together as they seem to like to hang out in positions where they face the same direction.
The Hujeta or Hydro gars get about 8 inches long in aquariums and I suggest at least a 60 gallon tank for them. The Needle Nosed gar gets to at least 12 inches and 100 gallons would be minimum I would think. length and width in a tank is better than depth due to the fact that these fish are long and somewhat inflexible and need room to turn.
These 2 types of gar are both beautiful but can be quite skittish, and if spooked can easily ram themselves so hard against the glass that they break off or seriously injure their snouts. They love eating feeder guppies and feeder goldfish, but I would ween them off this food for their main diet to something like freeze dried krill for two reasons. One is that feeder fish can carry parasites and you don't want to infect your fish, but the most important reason is that by hand feeding your gars will associate human presence with food and, will with time, be less prone to bolting and injuring themselves on the glass.
These fish are stalkers and like to lie just under the water surface. having plants, fake or real, that go to the surface is recommended. They are not very active and it's best not to keep them with Danios or other fish that swim around so vigorously as this activity can bother them.
Salt is also very important for most gars. I forget the recommended amount for a fresh water aquarium, but it may be 1 tablespoon for every 5 gallons of water. Check on that first though. The reason is that as gars mature they become more and more prone to getting bacterial infections and suddenly dieing. That was the sad demise of my 2 Needle Nosed gars.
I also had a South American Spotted gar that was quite beautiful. It had markings like that of a Rainbow trout with some pink on its underside. This fish should never have been sold for aquariums however as it was incredibly skittish and never tamed down like the Hujeta or the Needle Nosed. It was sad to see it freak when I walked by the tank and slam against the side of the tank. It eventually died I believe to a lack of salt in the tank.
You don't need so much salt that live plants can't grow. The amount recommended for fresh water tanks is fine.
To finish, if you are considering one of the North American gars such as the Florida or Florida Spotted gar, these fish get very very large. It's irresponsible to acquire one unless you have a 300, or better yet, a 500 gallon tank to keep them in. I myself have 2 Hujeta that are about 4 years old and 3 Florida Spotted gars that are about 9 months old. I have them all in a 100 gallon planted tank at the moment and I'm planning on building a mostly plywood 300-500 gallon tank soon. I've also taken the trouble of contacting 2 public aquariums in my area that have Florida Spotted gars and they will take mine if my plans for their future don't work out.
I wrote this up because there hasn't been much activity in the gar sub-forum recently. I've had about 4 years of experience with a few types of gars and I have some ideas that may be helpful for anyone intending to keep them. Some say the smaller Amazonian species such as the Hujeta and the Needle Nosed will not ween off live feeder fish, but I know that not to be true, and on the contrary I believe it's important to do so for the reasons given. You want your fish to see you as its meal bearer, not it's enemy. Freeze dried krill is my food of choice because it is very nutritious, floats on the surface, and it's a low density food, allowing them to eat more without over eating.