Love the spreadsheet! But yeah, double it lol
I have their 50 gal AIO. I set a budget of about $3k and I've exceeded $5k! That includes my water filtration/mixing and QT setups, though. Plus I'm a hopeless gear and automation junkie
The IM manual filter roller is still pre-order. And expensive. Check out this guy on Etsy... I believe he's here on the forums. He's got a larger version (for the 40 and 50) in testing now, and it's MUCH less expensive...
Shop items by iSeaLive.
www.etsy.com
I also got the InTank Aquatics fuge basket and filtration cover. The cover is a *MUST HAVE* if you wanna keep things looking neat and clean. I'm working on using one of the chambers for a small fuge.
I ended up using filter floss in the top compartment of the media basket that came with the tank instead of the white cotton balls. You could also replace the filter sock on the other side with the InTank filter floss holder, and have room beneath for more rubble or something.
inTank produces the highest quality filtration upgrades and provides expert advice for your Innovative Marine aquarium.
intankaquatics.com
If you go that direction, you may have to reach out to InTank to find out which of their products is the right size for your 40L since that one isn't listed specifically.
Best of luck, have fun, and post pics!