you may use the photo black ink as a substitute for the matte pigment black, the droplet size is bigger for this ink channel and you may see more stray droplets around letters, but do not use the matt pigment black in the dye photo black ink channel, that leads to clogging quickly.
The PG-243 cartridge contains Pigment Black ink only. It is used for text. Using Dye-based Black ink in the PG-243 that you use in your CL-244 cartridge will work but you will lose some sharpness of the font and water resistance. If you highlight text then it will likely smear.
As Ink Stained Fingers said, do not use Pigment Black ink in the CL-244. The pigment particles will clog the CL-244 cartridge's built in print head.
The MG3020 is a two cartridge printer using the PG-243/245/245XL pigment black cartridges and the CL-246/246XL tri-colour cartridge with CMY inks. No photo (dye) black is used.
Not all pigment black inks are suitable for refilling the black cartridge. @James Williams Maybe this is the reason for the question if dye black ink can be used in the pigment black cartridge? A suitable dye black ink can be used in the pigment black cartridge with good results, but I think it is necessary to remove the remnants of pigment black from the sponge before refilling with dye black. Mixing pigment and dye black ink might cause clogging.
See this thread about testing different inks and cleaning procedures for Canon combined sponge/printhead cartridges. Notice this post with recommendation of an ink set that works very well. These refill inks for the Canon two cartridge printersare available from Precision Colors.
If you need to remove the lid from a cartridge for cleaning the cartridge and sponges, a knife can be used, but beware, a knife slipping can hurt you. I once cut myself badly from a knife slipping when trying to open a cartridge. See this post for what I consider a safe way of opening a cartridge.
The reason I asked this question is that I just bought a refill package from Amazon.com. I didn't notice when I purchased the kit, that one of the 100ml. bottles is called "photo black" instead of just plain black ink. If I use the photo black to refill my black ink cartridge, I hope it doesn't cause a problem. Thanks!
I never try to open the cartridge with a knife. The way I refill my cartridges, is to peal the label off, and then drill holes to inject the ink with a hypo.
That is the normal and recommended procedure. But removing the lid and cleaning the sponges and print head separately can sometimes save a clogged cartridge, so it can be refilled and used once more.