It is important to choose the correct formulation of refill ink when refilling ink cartridges; otherwise the nozzles on the print heads can become blocked in time which will cause poor print quality.
For Epson printers with four or six cartridges we would recommend the following codes.. E830BK / E830C / E830M / E830Y / E830PC / E830PM. E830 ink is most stable for use with such printers. This is dye water based ink which is kinder to the printer heads than for example Pigment ink. However Pigment ink EP400 and EP600 resists fading and is preferred by photographers for longer lasting prints.
Eight and nine colour printers use extra colours to increase the colour gamut. To refill Epson Stylus Photo R800 and R1800 tanks you should use ER800 series refilling inks. These also include ER800GO Gloss Optimizer, ER800R Red, ER800B Blue, ER800PBK Photo Black, ER800MBK Matte Black. For the R2880 the correct formula re-order code is E9888 including E9888PBK Photo Black, E9888LBK Light Black, E9888 Light Light Black.
The above inks are available from https://premium-inks.com/collections/epson-dye-printer-refill-ink/products/800ml-dye-ciss-refill-printer-ink-bottles-epson-stylus-photo-r800-r1800-non-oem and other products from the home page at https://premium-inks.com