Your explanation is perfectly understandable. The extra knot hole & the added chimney is a great addition. Preferably you'd want the heater either near the intake or the outflow. Is the heater fully submersible? If it is you could always lay it lengthwise at the base behind something like plants. You would then have to just hide the cord. If it's not a fully submersible heater then it's gonna be sticking up partially above the water line somewhere.
Anyway so far it's looking great. Keep up the good work.
Thank you!
Hmm... I could do that. I have a 200 watt heater (The rule is 2 watts per gallon, right or am I thinking of lighting fixtures?), but it can't be submerged. The top has to stay above the water line. The only place I see to put it would be near the filter intake. Thanks for your help!
Looks pretty good so far mang. 
On the reverse of the wall, are you going to carve out a channel for the filter flow, or just carve an open space, or maybe use a PVC channel for the filter intake water to flow through? I've seen similar designs where the heaters were hidden behind the wall either in a carved out channel, a sump area or within a 2" diameter PVC tube. You could come up with a design to suit using a submersible heater as long as there's plenty of water flow and the heater isn't touching the foam.
Also, think about the filter you want to use. There are some canister filters and HOB filters that can accommodate a heater within them out there as well. The higher end Eheim Pro II & Pro III filters have a built in heater, the rainbow lifeguard filters have a heater module, and some of the tetra tec HOB filters have heater modules.
Thank you!
I already have a filter that I am planning that came with the tank. It is an Aqua Tech 30-60. It came with a plastic tube connected to the intake that is pretty long. I was just going to stick the intake plastic tube down deep in the channels I carved from the Styrofoam, hoping that the current will be pushed into the channels because of the suction of the filter intake.
As for the outtake, I will be carving a "slide" from the lip of the outtake down into the water at a slope not so steep so it reduces the trickling sound when it falls from the lip into the tank water, however I will have a bubble tube in there so that there is some surface agitation for more oxygen to be dissolved into the water.
These are two pics of my filter just for better understanding since I am not someone with a keen ability in explanations. (by the way, I am going to clean it out, because it is VERY messy)
And here it is when the Styrofoam is in it.
You can flash back to the first page to see a diagram of my intentions.
Basically, I am just going to stick the intake tube down into the channel and hopefully it will cause enough current to make water go through the hole on the opposite side of the tank because of the higher pressure in front of the background than in the back. If I could turn the entire tank around and show you what it looks like with the channels and the filter working together, I would, but I'm pretty much alone on the project and moving a 55 gallon tank is a two person job.
