querries regarding saltwater aquarium

i'm new to this hobby and currently i have a small freshwater aquarium.but in the near future i want to have a big aquarium where i want to keep both fresh water as well as saltwater fishes.as i'm a new hobbist,can anybody suggest what should be the ideal length of the tank and necessary steps so that i can maintain my tank successfully in the long run.i will be very much pleased if anyone can suggest me.

Welcome to our forum. The best way to start in the hobby is to make it simple and cheap. A 20 or 30 gallon aquarium is good for most freshwater fish. Before adding fish, make sure to fully cycle the aquarium. Some inexpensive, live plants will help. The most common mistakes are over crowding, over feeding and species incompatibility. Once the aquarium is cycled, add one or two pairs of live bearing fish like Platies or Guppies. A single species aquarium is easier to keep. If you prefer, you can buy some of the more common egg laying fish. The idea is to provide ideal conditions for the fish, and let nature do the rest. Saltwater tanks are more complicated and expensive, so you should wait until you have some experience with freshwater. Aquarium keeping is more complicated that you may think, but those suggestions are a good starting point. Please feel free to ask more questions.

since you also live here in india u'll have to send me more pm so that i can interact with you....the min length of aquarium will be 3 ft*1.5 ft* 1.5 ft..and oniously a little bit planted...you tell me the name of fish that you want to keep and i 'll tell are they'll be okay or not..

Welcome, do you mean you want to keep both fresh and saltwater fish in the same tank together?

i want to have a big aquarium where i want to keep both fresh water as well as saltwater fishes.

These fish have totally different requirements as well as different organs for dealing with the difference in salinity. The only freshwater fish you may be able to keep in a salt tank is the molly. They can be acclimated to both and actually do better with some salt than with totally fresh water. If this is not what you meant then at least I hope you learned something cool about mollys.

hm i agree with you miss megham ,you also agree that freshwater fish likes living plants where as saltwater fish likes rocks,obviously they are differece in nature,likes and dislikes.. even the plants and foodings and even the filtering system varry for saltwater and freshwater fishes..