Think dry walling the ceiling was what I planned to do, just hadn'yt got round to researching enough to see what it was called 

Thanks for the info SK, I will look into it, I'll be honest though, I don't know if its got any ventilation, other than the gaps in the metal doors. My plan, as I am not that fussed about paying a little extra electricity, was to keep the gaps at the top of the overhead lift front doors for ventilation. I know this would cause extra heating costs in winter where it gets to about -2/3 at worst, but it seems silly to add a big vent system when this is already doing the job? That may sound daft to someone who knows better, it just seems to make sense to me, but as I say, I know nothing on this stuff really
Also, just to clarify, there wont be that many tanks in here, when I say a fishroom, I will be keeping about 4 or 5 show tanks, and a couple of breeding, there certainly wont be anymore than 10 tanks, hopefully about 5 of those will be 40gallons an less. The big tank however will hold hopefully well over 1000 Gallons. It wont be your typical fishroom with rows an rows of tanks
hello; The issue will come about if you cover the ceiling with drywall or some other material. This will create a space above which could be called an attic. It has been my understanding the garage is to be insulated and insulation on the ceiling is where the most savings will come. The idea is that the space above that insulation and under the roof should be vented. As the roof will be cold there will be a lot of condensation in that attic even from the few tanks you describe.
One way to avoid the issue is to not drywall the ceiling but instead spray foam under the roof itself. This will likely give a better insulation effect and avoid the dead air space. I suppose you could also put batt insulation between the top roof boards and add a vapor barrier over that and save some cash.
If you drywall the ceiling, then the gap over the top of the doors seems unlikely to help with the attic space. It will not take long for the expense of heating to overtake the cost of sealing the gaps around the doors and a proper insulation job. Also the cost of this heating will be ongoing while the insulation will pay off over time.
It seems you need someone who knows this stuff to give you some onsite pointers.
hello; The issue will come about if you cover the ceiling with drywall or some other material. This will create a space above which could be called an attic. It has been my understanding the garage is to be insulated and insulation on the ceiling is where the most savings will come. The idea is that the space above that insulation and under the roof should be vented. As the roof will be cold there will be a lot of condensation in that attic even from the few tanks you describe.
One way to avoid the issue is to not drywall the ceiling but instead spray foam under the roof itself. This will likely give a better insulation effect and avoid the dead air space. I suppose you could also put batt insulation between the top roof boards and add a vapor barrier over that and save some cash.
If you drywall the ceiling, then the gap over the top of the doors seems unlikely to help with the attic space. It will not take long for the expense of heating to overtake the cost of sealing the gaps around the doors and a proper insulation job. Also the cost of this heating will be ongoing while the insulation will pay off over time.
It seems you need someone who knows this stuff to give you some onsite pointers.
Hello; Not sure what you are saying. The number of tanks you describe will make a lot of moisture in the air. It will also take some cost to heat that much water in an uninsulated garage.
Good luck
I have my fishroom in a basement. It had a concrete floor that got very cold (before I moved the fish in). I put treated 2 x 4 on the floor (nailed to the cement with special fasteners), 16 inches on center. Then I cut 1.5 inch styrofoam sheets to fit between the 2 x 4. Then I put 3/4" inch plywood and vynyl flooring over that. It was very labor intensive and kind of expensive, but it makes a difference.
You are right, you really need to insulate the floor, ceiling and walls to get maximum benefit, especially the ceiling, as heat rises. But if you can't do the floor, do what you can.
Insulation makes a huge difference. I have the water heater in my fish room and the furnace. I have no vents from the furnace. Well insulated, and an exterior door closes it off. The rest of the basement is maybe around 60 F in the summer, but the fish room stays at 80-82, with just the background heat from lights, water heater, and furnace (no vents from furnace).