I will be setting up a 90 gal tank system I am picking up this weekend. It is a fully running system but from my research the return pump now must be old as I can't find anywhere to purchase one and all posts about it are from 2012-2013. I know that is the most important thing and I don't want it to crap out on me at random so I would feel better knowing I have a new pump, even if everything else is used. It is a Waveline DC5000 return pump. Any suggestions on an economical, reliable option to replace it with? Not looking for all the bells and whistles. Budget $100. Also this will be my first time using a sump so any tips would be great.