In the next couple of weeks, I will be plumbing PVC from the dining room through to the garage. The kitchen to the garage will have a 3-4 foot drop. With the tank elevated in the Garage, the high of the sump will be about a foot lower than the dining room. My goal is to keep the plumbing as simple as possible, 1 up 1 down plus and emergency drain. There will be two 1.5" drain pipe and one 1" return. Here are some of my questions: <li>If I run horizontal pvc through the wall, what are my options to fill the wall gaps and the holes? Do I use spray foam or are there fittings available? <li>Rather than using horizontal pvc through the wall (been reading that using 90 elbows and horizontals are not the best solutions), should I use spa flex? <li>If I use flex spa, should I make a big square cut out and stuff all the pipes through? Are the boxes available for this type of projects? If anyone has any experience or suggestions, please let me know. Thanks in advance.