[StirCrazy]

Originally Posted by Kramer

Cold water systems have few if any Photosynthetic organisms in them so heat from a large lighting system won't be a problem. Heat from circulation could be. You could allows limit it by running a closed loop instead of internal pumps.

I would just use the money you save on lighting and get a chiller right away.

well not really, considering almost all the neat stuff you want to keep in there is non photosynthetic they feed on things that are like algae (hence the dark greenish color of our water compared to down south, a lot more algae, which in turn translates to heavy algae type plank-tonic feeding which mean big heavy skimming to keep the water quality.

as for chillers a small one won't be enuf, you are looking at an aproximat 30 degree pull down for 30 gal of water and more if ther eis a sump ect.

Diana couple problems, around the Island where ever there is a good water flush the average temp in the summer rarely goes over 55 and if it does as in tidal pools it is not for a long time, so in reality you need a chiller to keep water temp under 60 degrees to be successful in the long run. also as mentions above tons of skimming/filtration and good lighting to actually keep food sources alive for the filter feeders. after you do all this you won't be able to see in your tank due to all the condensation so you will have to run out and buy an acrylic double walled tank to take care of this.. also the fact that it is more expensive to cool a tank via a chiller than to heat it with a heater by a large amount, see where I am going.. to do a proper "cold" water tank it is very expensive, but if you are fin with that it can be very rewarding as I know where there is some feather dusters I would love to have in my tank, they are purple and steel Grey striped and out of this world, but I digress. Look into it a lot more as you may decide that isn't what you expected.

Steve