Monthly upkeep costs for your system?

[Myka]

I agree that a 4' tank is too small for a FOWLR. The cost of a FOWLR is much less than a reef because you aren't paying so much electricity for powerful lighting. after startup costs, the costs of maintaining a FOWLR aren't very significant. You would mainly be looking at electricity, food, and salt. Keep costs down by buying things like carbon in bulk from www.bulkreefsupply.com

You can figure out electrical costs fairly accurately by using an online electrical consumption calculator. Find out what a kWh costs in your area, and then look up the wattage of the equipment you will be using. My 90-gallon reef costs me about $40/month in electricity at 11.35 cents per kWh running 250w halides, skimmer, return pump, heater, powerheads, etc.

A bucket of salt lasts me about 4 months, so that's 3 buckets per year doing 10% weekly waterchanges. IO is perfectly fine for a FOWLR and it's cheap, but you may need to do bigger waterchanges on FOWLR, although a really good skimmer would help reduce waterchanges. Heaters can cost a lot of electricity if the tank is in a cool part of the house (basement?). Pay attention to electrical usage when you're picking pumps and skimmer.