I am about to plumb the return for my 120 gallon tank and I am considering using two pumps. At first I was just going to use one return pump and have it to go through a spray bar. After seeing a timer that has 15 minute intervals I thought it might be a good idea to alternate between two pumps with two different spray bars every 15 minutes to give it a nice chaotic flow. Would this be a good idea or would it be better to stick with 1 pump and 1 spray bar. As for the spray bars I would probably mount them veritcally at the front left and back left of the tank or both horizontly with one agaisnt the front wall and one against the back.
Question 2. I would like to run an external pump (or 2) because they add less heat to the water than the larger mags (I have heard) which I would have to use other wise. My problem is if I go external I am going to have to mount them above the sump, about a foot above the water line are any of the externals not gravity feed? And if so how much head height would it take away having them above the water and having to pull it up? If a submersible won't add that much heat it would probably be easier in my situation, but I like the benifits of an external, flow, quietness, less heat, only problem is for the price of some externals I could get 2 mags that all have the same flow. Then i'd have to double the price of one external. lol
Thanks for all the help. Sorry for the long post. I felt like typing