wow there your discus eat better than me, because i only eat one meal a day and during the day i only eat a ftira .:). Well you seem to have all the parameters correct. Just a couple of things, if you fill the water in a container a day before and leave it open for 24 hours you will get rid of the clorine as it evaporates. Another thing, if you are doing a big water change make sure you warm up the water beforehand.As i rule i do not do a water change everyday but only once a week. I only do frequent water changes if there is something wrong with the fish. If you are going to get another discus, do not just buy one but at least two. The thing is that the one you have now will probably bully the other one, so if you get two the agression will be split into two. Discus love being in a shoal. You can add some tetras too. like rummynose.
One final thing i am not too sure about have a pleco that size with the discus, but if your discus was scared it would not be eating. However it seems to me too big a fish. Having said that, i have a real big and two other smaller clown loaches in my discus tank and so far no trouble. So maybe after all the pleco is harmless. A suggestion, i would buy a couple of large plastic plants and put them infront of the filter so as to hide it a bit. or else a piece of bogwood
hope we see you soon at the club