Tank Placement

How far away should a tank be away from a window that includes reef, fish, and invertebrates?

close to window is not the issue it is the direct sunlight you do NOT want. it will fuel algea blooms and heat issues. or atleast it has on my first tank. i would keep away from the direct sunlight. ok fellow reefers add some more useful information

I would be concerned about temperature swings. A door would be more of a problem but assuming the window is closed this time of year you should be able to take a good guess if it would be a problem by pacing your hand near the window. If you are almost touching it before it feels cold you should be OK.

:Welcome) to DRC!

Its a matter of opinion as to how much sunlight matters, but I would definatley be worried about temp swings because of a draft in the winter if they arent that new, as well as extra heat in the summer. I would say at least a couple feet… but that depends. Ours butts right against the two windows on the wall it shares, but the blinds are almost always drawn. As long as it isnt right in front of a window you should be fine.


Many people have purposely put there tanks near the window to try to use some natural light. Most of the time as Glenn mentioned it will cause more algea growth then anything else, but some have had good results.(faster growing healthier looking corals) The temp thing can be a problem if the window or door are not sealed too well in the winter. Wouldn’t matter much if the door was opening and closing because a couple of minutes of cold near the tank would not chill the large volume of water of a reef tank.(takes a lot of energy or lack of energy to change the temp of salt water)

Once again welcome to the boards. Any chance you’ll be able to make it out to any of our meetings? Should think about making another post and introducing yourself.

One of the bigger problems with placing a tank near a window is sunlight. Aside from temperature issues with older windows, newer windows will pose their own problems.

New windows are all made with UV coating to block UV rays. the problem is that the UV rays that it does allow to penetrate seem to be the same rays that fuel algae growth. Along with this is the afore mentioned temperature issues from placing a tnak in direct sunlight, the tank does not need to heat up much to cause issues, algae will grow better in warmer water (even 1degree can make a huge difference) so combined with the UV issues you could find yourself constantly battling algae.