Water changes serve an important role in your tank, yet you either love them, or hate them. I’m in the “love them “camp and when I’m designing a tank for a client, I’m often asked to make water changes as easy as possible.
The main role a water change plays is to export nutrients out of your saltwater tank. By removing existing water out of your system and replacing it with fresh saltwater, nutrient levels are reduced and other important levels (calcium, magnesium, trace elements, etc) are increased. Here’s the key thing to note about the reduction of the nutrient levels though: unless a large (50% or better) water change is performed, you’re not going to reduce nutrient levels by a large amount. I often see people post about having a high phosphate or nitrate levels and the advice given is to a 10-20% water change. The water change won’t hurt and it isn’t going to provide the large drop in levels that the person is likely looking for.
Why even do water changes then if they aren’t useful unless the quantity of water removed is large? Several reasons:
- Replenishment of elements. Until a tank is well stocked with growing (emphasis on growing) corals, calcium, magnesium and alkalinity levels can be maintained simply through water changes.
- Good habits. When you are doing a water change, you have to pay attention to your tank as you are turning pumps on/off, removing water, etc. The water change exercise is a great time to look over your tank to make sure everything is looking good and running well. Maintaining a weekly water change routine forces you to give your tank a good look over which will help catch any problems faster.
Of course people always ask if they can never do a water change and still maintain a saltwater tank and the answer is “yes”. Some tanks do fine on zero water changes. I’m not a fan of the zero water change method as I enjoy water change days and all the hands-on-the-tank activities that come with it. As I write in all my books, there are many ways of setting up and maintaining a saltwater tank. My way isn’t the only way and it is the way that has worked for me and my clients time and time again.Browse the Store! Questions?