Do you know what kind of house plant is it? Most problems people have with houseplants is that they over water. Once a week, could be too little though depending on the moisture in your house. If you have a wood burner, moisture is especially taken up quickly in the winter. You usually have to water more often than normal. I've had plants that require watering daily. The pot also plays a large factor in how quickly the moisture is taken out of the soil. I'd google the plant and research it a bit before growing. Being that you have brown tips, my guess in your case is that your plant is drying too much in between watering. Feel the soil with your finger each day and when it is dry to touch soak it. Put them in the shower too sometimes to clean them off and give humidity. It is good once in awhile to flush out the soil to get out the excessive minerals. You can tell when you see alot of white around the pots and on the soil. Try to replicate what conditions are like in the tropics. As far as sunlight goes, research what footcandles are and determine how many your plant requires. You can put a hand a 12" away against a piece of white paper and this will show you how strong the sunlight is. You could probably google this. Remember that in the tropics, most houseplants are in the understory and are not in direct sunlight.
I have two horticulture degrees
· 1 decade ago