DIY Rock Columns to hide equipment in cichlid tank

[Munchie]

I have a 5' 100 Gallon african cichlid tank. I use a eheim canister filter, a Koralia 850 and a Marinelane 1200gph powerhead. My goal with this project is to hide this equipment in the tank and blend it in with the universal rocks background I have in place.

Here is a quick mockup I did in photoshop to explain what I am thinking.. Do you see any issues with this?

I have 2 4" diameter lengths of PVC pipe and a can of pond foam (the black stuff) I plan on using small stones and sand in addition to the pond foam and then the plastic spray paint to give it the coloring I want. Do I have to seal it additionally?

Will placing my canister filter inlet in a "overflow" type setting cause issues?

Would love feedback..

 

[Munchie]

I opted not to use PVC- instead I grabbed vinyl gutter gaurds



A 3lb piece of dry rock should keep it from floating