Hobbiecolor with my I9900 also has a green cast, but with ProfilePrisim and now PrintFix Pro profiles the prints are way better than Canon Ink and stock profiles.
Welcom to the forum.
Refilling for the ip4000 is the way to go, CIS for canon printers is hit or miss, mostly miss. with refilling so easy for the Canon it is not worth the effort and cost to us a CIS, (been there done that)
I love Hobbiecolors get the 5 color kit...
spectrophotometer is the short answer.
There are several ways on the market to profile printersand have different names. On the cheep side is a scanner based system Prifile Prisim $69 the latest software vertion make very acceptable profiles. For $500 or less you can get new PrintfixPro witch...
I contact him through email found on Hobbicolors.com to avoid ebay ( I don't have an account there ). He has allways gotten back to me in a matter of hours. Orderd Sunday nite and got notice of shipment first thing Monday morning. Dave and his products are great.
I bought 2 Hobbicolor kits for my I9900 and filled the virgin carts with thier ink. I figured the carts alone were worth the cost so the ink was free, if the ink didn't work oh well.
My results are: The screew on the carts works fine with out a o-ring (I'll have to wait and see if this changes)...