I have been asked this a lot recently… “why do we have to perform water changes in our planted aquariums?”
Well, we all know it has to be done…but here’s the reason why in a nutshell: It greatly reduces your chance of algae and increases your chance of success at growing plants!
Now here’s the long story. As your plants grow they use many elements such as light energy, CO2 and nutrients to fuel growth. Just like all living things that need fuel to live, there are always waste products. Plants are no different and the quicker they grow the more waste they produce (makes sense right?). This waste MUST be removed somehow: Enter water changes. In an enclosed environment such as an aquarium, all these excess waste products need to be removed somehow and the only way of doing this is changing the water with fresh clean water from your tap. Remember to always de-chlorinate your water by letting it stand for 24 hours, this will also bring it to room temperature (important for your fish!).
The rate at which we need to carry out water changes is determined by how quick your plants grow. What do plants need to grow? Light, CO2 and nutrients. The more we add the quicker they grow. The quicker they grow the more waste they produce…and therefore more frequent water changes are required! This is why in high tech set-ups with high light and high levels of fertilization, frequent water changes become more crucial.
Why do we have to remove of this waste anyhow? The waste that plants produce soon build up over time and are food for algae. The higher the concentration of these pollutants the more algae will thrive. It’s important to note that you cannot actually see these pollutants, you just need to know THEY ARE THERE. With no escape in such an enclosed environment such as an aquarium, these pollutants have nowhere to go unless we perform water changes.
Try conducting 40-50% water changes per week. This will effectively dilute your aquarium water with fresh clean water, thus decreasing the concentration of pollutants. You plants will thank you for it, trust me! In highly lit aquariums, twice weekly water changes are a good idea (more light = faster growth = more waste).
On a final note: I further recommend carrying out a minimum of 2 water changes per week during the first 3-4 weeks of a newly planted aquarium. Your aquarium is yet to mature and plants have yet to settle in. There is a lot more waste produced during this initial stage, so carry out more water changes until things have settled in. Please contact me on firstname.lastname@example.org if you have any questions, or leave me a comment 🙂