It can be profitable if:
1) You will be servicing saltwater/reef systems -- the reason is that many people who own these don't have the skill, desire, or time to maintain them. At the same time considering how much money can be invested into such set up they will be willing to pay top $$ to anyone who can do a job
2) Businesses -- most hobyists will dotheir own tanks. Business on the other hand fall into the same category as above. They are rather pay you for maintenance than to have an unsightly tank (can be a big turn off for cutomers)
3) Research is a must just like with any other venture -- how many LFS do you have in your area? Are they doing well? If not, this could be an indication that local residents are not into fish keepeing
4) How will you advertise? A word of mouth? Print media? TV? Etc?
5) Cost of equipment -- figure out what your start up capital is (please dont fool yourself by thinking that you can get a business started with nothing but a couple of buckets, an old python hose and a dodge neon you drive on weekends. You may want to invest in a powerfull RO unit to produce your own water for saltwater and discuss tanks
6) Legality -- will you register a corporation? You will need some sort of a liability insurance to protect you from potential lawsuits that can result from fish dying after your service or a tank springing a leak. Also, be ready for your autoinsurance to jump up if you assign your car to be a business vehicle
7) Make sure you befriend a shrink -- doing tank maintenance for business is not the same as cleaning your own tank. Customers will give you hell and will drive you up the wall. Plus, you will not always succeed in telling them that their oscar cannot be kept in a 20 gallon tank. Many will get upset and wont use your service any longer. You willalso be blamed for just about every unexplained fish death
I think its a great idea but you in order to succeed you must approach it like a business venture from the beginning
