Snake's Methods for Reducing Nitrates and Phosphates Many of you who keep corals number one goal is water quality control. What is it that we mean by reducing nitrate and phosphate anyway, and what is nitrate and phosphate? Well, this article will discuss what it is, and what it means for your aquarium and the health of your livestock. Nitrate is the product of the Nitrogen Cycle, which is discussed in quite some detail in other articles. There is and always will be nitrate in everyone's aquarium. The natural biological processes of the creatures we have in our tanks often produce ammonia which keeps the nitrogen cycle constantly going. Nitrate in the wild is taken up by algae. Algae is fed upon by higher living organisms, and it forms the base for the circle of life. Phosphate is a pollutant and fertilizer that enters our tanks via food we feed our fish, some chemicals we use, and bad top off water or saltwater we buy. Phosphate fuels algal growth and is harmful to the health of corals. In our aquariums, we have access to many different types of equipment that allow us to control the amount of nitrate and phosphate in our aquariums. There are many sources of information about the details on what nitrate and phosphate is, which go into more depth than what I can personally do. I encourage you to do your own research on nitrate and phosphate so you have a better understanding of what it is. Nitrate and phosphate usually go hand in hand. It's one of those things where if you find one, you will find the other. Nitrate and phosphate can sometimes give false readings of their presence in saltwater aquaria because of algae that may be growing in the system. Algae have the ability to “fix” nitrate and phosphate into their tissues to fuel their growth. This is why when there is the presence of nitrate and phosphate in your aquarium, it will grow algae under the right conditions. Before we get started discussing the basics of how to reduce nitrate and phosphate, I want to go ahead and say that none of this will make a bit of difference if you don't already use the proper aquarium husbandry techniques in the first place. You can find a link to my thread about it here. These are my methods for reducing nitrate and phosphate over the years. These are my personal findings, and what works for me may not necessarily work for you. I highly encourage everyone who reads this to do separate research on the subject. Now that my disclaimer is over, I'll move on to the basics. The BASICS for how to reduce nitrate and phosphate in the absence of algae (GHA or other.) [list type=decimal] [*] Water changes are a must. There is no better way to immediately get some relief for your livestock than to do water changes. If nitrate is above 100ppm and phosphate is above 5.0ppm, a 50% water change every week until the numbers come down. If nitrate is less than 10ppm and phosphate less than 1.0ppm then 20% weekly water changes will do, until the numbers start coming down. [*] Before you do a water change, take a turkey baster and suck up all of the cyanobacteria out of your tank. You can even use an airline tube. It's kind of the process before doing a water change. Detritus can be blown off the rocks and into the water column for your filters to start filtering some of it out. While it's stirred in the water column, do your water change. How to reduce nitrate and phosphate in the presence of algae when your test kits read zero: Research the type of algae you have in your display tank and ways to get rid of it. Water changes will not decrease or eliminate the algae in the display tank. I highly suggest you read my thread on getting rid of hair algae. You can find that thread here. You must first address your algae problem. Once the algae is gone, then you can decide if nitrate and phosphate can be reduced by water changes. If you took a chemical fix and your algae has died, then nitrate and phosphate has leached back into the aquarium and must be dealt with by water changes, protein skimming and nitrate and phosphate sponges. [/list type=decimal] Equipment! I love equipment! Next to livestock, it's perhaps one of the most exciting things in this hobby to me. I like the little gadgets and gizmo's, and I have tried a lot of them, but they all don't do a very good job and as the saying goes, often you get what you pay for. So, what equipment can you use to reduce your nitrate and phosphate in your system? Protein skimmers are often thought of as an absolute necessity for keeping a saltwater aquarium clean and algae free. Protein skimmers remove dissolved and particulate organic matter from the water column before it has a chance to break down into nitrate and phosphate. They utilize bubbles that come in contact with the saltwater. The bubbles attract dirt, debris and organic compounds that stick to the bubbles. The bubbles then rise to the top of the chamber and collect in a cup. The cup can get quite dirty and stinky in a matter of days. The darker and the more gunk that is collected in the cup – the better the skimmer. Protein skimmers can take up quite a bit of real estate in the back of the aquarium or in the sump. Protein skimmers, like any piece of equipment have their place in a saltwater aquarium. Sometimes, an aquarium needs a protein skimmer badly, depending on the bioload of the aquarium and what other filtration media is being used. ight: normal;"> Algae Scrubbers are not new to saltwater aquariums. They first started in commercial applications as a way to reduce nitrate and phosphate by way of growing algae on a screen. The algae would then be cleaned, collected and removed from the screen. By removing the algae, you remove nitrate and phosphates from the system. Algae scrubbers are highly efficient at reducing nitrate and phosphate in a home aquarium and there are many reasons for utilizing one in your own setup. More information about algae scrubber can be found on my thread Algae Scrubber Basics found here. Chemical Filtration is often used in applications where protein skimming is not enough, and algae scrubbers can not be used on the setup. Chemical filtration medias including Nitrate and Phosphate removal media, are, in my opinion, a band-aid (adhesive bandage? I buy the cheap stuff...) to a problem that can otherwise be dealt with by water changes. In high-feeding situations such as NPS tanks, even GFO isn't enough and there are other ways of collecting and removing nitrate and phosphate. Refugiums growing macroalgae is also something to look into if you want to reduce your nitrate and phosphate. There are a lot of variety of algaes that do a very good job at reducing or eliminating nitrate and phosphate from a system. If you have the extra space in your sump, or an extra drilled aquarium, I highly recommend to use a refugium. A refugium grows macroalgae which has the same principles as using an algae scrubber. (Although algae scrubbers will out-compete macroalgaes for nutrients.) A refugium also can be used to add additional water volume to the system and a “refuge” for invertebrates such as copepods to live and reproduce. Refugiums also allow additional live rock into the system which has it's own ability to filter the water. Really Deep Sand Beds were once really popular a few years ago. Many argued that you should keep a 4”+ deep sand bed in your display tank, while others argued against it – and the debate goes on. From research, we know that deep sand beds that are six inches or deeper have the ability to build up anaerobic bacteria to convert nitrate into nitrogen gas. However, over time hydrogen sulfide is built up. If you have ever seen an aquarium with a really deep sand bed, and it has black striations across the bed, that is a deadly poison called hydrogen sulfate. It kind of smells like rotten eggs if you stir it up. Hydrogen sulfate is deadly to a tanks inhabitants. Therefore, I no longer recommend deep sand beds in a display tank. Instead, I recommend remote really deep sand beds that are no less than 10” deep, and I recommend to keep them in pairs. Once every two years, you clean one of them out and rotate them out. Clean it or even replace the sand to keep it from building up the deadly hydrogen sulfate. I will create a thread on how to build a remote deep sand bed and their benefits and detriments soon. Water Changes of course, is the old stand-by. A good 50% water change will reduce nitrates and phosphates in the tank and replace major and minor elements in the aquarium. It should also balance your chemicals naturally, without any intervention, as long as you have a good, high quality salt. 0in; font-weight: normal;"> MY METHODS: [list type=decimal] [*] I use protein skimming in really heavily stocked reef aquariums with high bioloads in combination with a refugium and/or algae scrubber. I also do one, 20% water change on these kinds of tanks per month. [*] I use protein skimmers on fish only with live rock tanks that have no corals or inverts and low lighting. If nitrates get above 50ppm, I'll usually step in and do a water change when it's needed. [*] I use only oversized algae scrubbers on reef tanks with medium-high or less bioloads. Usually, on these kinds of tanks, I'll monitor nitrate, phosphate, calcium, alkalinity, and magnesium and decide if they need a water change. Usually, I'll do a 50% water change once every six months to a year on these types of tanks. On really low bioload tanks, I won't use anything but a nice filter and do some water changes. If everything stays the same, and I use a high quality salt, then these types of tanks generally don't require additional protein skimmers or algae scrubbers. In broodstock tanks, they each have their own sump and protein skimmer. Sometimes, these tanks will get a fuge or algae scrubber. Most fish will tolerate nitrate and phosphates and still breed. They also have their separate systems to prevent the spread of disease. [/list type=decimal] Let it be noted that some corals such as Xenia and mushrooms like to have a bit of nitrate and phosphate in the water column. If the tank is too clean, sometimes Xenia does not do so well, or even dies off. Mushrooms are somewhat the same way. SPS corals and some LPS corals require extremely clean water, which is something that most aquarist strive for.