Filtration set up advice

[99gtbaby]

What would I have to change to use a sump instead of a Fluval fx6 and Fluval 407? Display tank is 125 gallons, I want the sump tank to be 55 gallons. Any advice on setting up a divider/baffle free sump tank? Can I successfully set up a sump for less than what a Fluval fx6 costs if I already have a 55 gallon tank to use? Because if I can do that instead of purchasing the fx6 then I would prefer to do that, but also keep the Fluval 407 since I already have that. Could I place the intake of the 407 into the sump and then the outlet into my display tank and use that as my return system from sump to display tank? The flow on the 407 can be adjusted. I do plan for corals in the future so I know that needs to be taken into consideration as well.

 

[T-J]

I'm having a hard time following your diagram. But, I'll try to answer your question...

A sump can be pretty much anything that holds water. When I started 20+ years ago, my first sump was just another plain aquarium. Later I added baffles. After that, I went to two giant rubbermaid horse troughs as my sump/refugium and grow out tanks.

So yes, you can use just a plain aquarium as a sump. Just make sure you have enough room in it when your pumps are off (just like any other sump).

If I'm reading your drawing correctly, DP is your display? If so, you'll want your ATO running to your sump, not your display. Actually, I suggest running everything into the sump instead of the display except for your overflow and return lines. Keeps minimal amount of items in your display, and a central location for all of the lines/plumbing in the sump.