One thing you can do (if you don't have a soft water aquarium to provide lovely fertilizer enriched water, like I do) is to utilize mild fertilizers into the water you give your plants. Do you drink milk? Do you recycle the jugs? After you have emptied the jug, if you can swish around in there with good soft (not softened!!!) water you'll pick up some protein, etc that will be a mild fertilizer. Don't pour milk on your plants! That would probably start to smell bad.
I have not done it, but if you collected your own urine and then diluted that quite a bit, that might be a nice fertilizer for your house plants. You might want to search on urine + fertilize here on these forums for more info.
If you have hard water you can get a buildup of salts in your potting soil that is hard on your plants. Usually you can see white crusty powder on the soil surface or maybe the outside of a terra cotta pot. In that case, some people repot. We have hard water in Wisconsin, so I use either rainwater or water from our aquarium, which is RO (reverse osmosis) filtered, for our plants.
If you are in an apartment, you could have a little worm box and then collect the "tea" from that--this would be an excellent fertilizer for a house plant. The worm castings would also be terrific for sprucing up the potting soil.