I have a 55 gallon tank with a large bala shark in it. The fish is approximately 5 years old. Today I noticed the shark gulping air, rather loudly, at the top of the tank. I have never observed this behavior before. Is this normal? There are several other fish in the tank as well and they all seem to be acting normally. Thanks!

First of all, good for you for keeping them in a big tank like they need. I'm so sick of telling people they can't keep them in 10 gallon tanks with redtails and rainbow sharks, its unbelievable. Kudos :) If it was right after a waterchange, that this happened, it is probable that it has something to do with the new water. I doubt their gills got clogged...bala sharks are pretty sensitive to water params, and gasping can be a sign of poison, but along with other things. I suggest you test your tap water for ammonia, nitrite and nitrate. Test for pH too, just incase your water supply company decided to meddle with it (this happened to me recently, but out of pure pure luck I tested the tap as they were changing it...and I hardly ever test the tap pH). If you have any way to test your water for chlorine, definately do that. Water companies often add a strong dose of chlorine to clean the water every once and a while, so if you can't test for chlorine or other metals, add a huge dose of water conditioner to your tank and call to see if you can find out. I'm sorry about your sharks :( Bala sharks truly are magestic creatures that rarely find knowlegable owners with suitable living quarters. Yours did, but its a shame they didn't make it...

Balas are stricly tropical fish, native to SE Asia and require water never less than about 72 deg., so you would need quite a pond heater. Also, while they are attractive when viewed from the front, from above, they would look pretty much like oversized minnows. They also get quite large, up to 16" and in a large pond, might exceed even that. They also need to be kept in schools, or they become very aggressive. If your pond will exceed 1,000 gal, are you sure you don't want some nice Koi? Or, for a smaller pond, Pond Comets, or Wakin? The Koi and Wakin especially, are most attractive when viewed from above. But mainly, they will also winter in a pond with only an air hole in the ice and with some patience on the owner's part, will become very tame and confiding. However, if you are bound and determined to keep tropicals in a garden pond in an area that freezes and are thinking of a greenhouse as well, your obvious solution is a real, working, heated greenhouse with a pool in it. Otherwise, you should plan on a very large tank somewhere in a heated area for winter, because it takes a huge amount of energy for tank heaters to produce a temp. rise more than about 8 - 10 deg. above ambient air temp. If you do some web searches on aquarium tank heaters, you will find interesting articles on how water temps affect fish, and charts, to tell you how much wattage per gallon of water in relation to ambiant air temp is necessary to maintain the proper temps for tropicals.

Is your name Rodney McKay (StarGate Atlantis)! Sounds good! Here is a link that might be useful: Am I GOOD or what