The nitrogen cycle is very well known because of its study in both growing crops and waste water treatment. Nitrogen is one of the dominant gases in the air we breathe and it is also a key part of the nutrient cycle. Nitrogen compounds in aqueous environments predominantly include ammonia, nitrite, nitrate and nitrogen gas.
There are four basic forms of nitrogen that we are discussing here;
- Nitrogen (gas)- N2
- Ammonia (gas or dissolved in liquid) –NH3
- Nitrite (dissolved in water, very toxic to fish) – NO2
- Nitrate (dissolved in water) – NO3
Nitrogen gas is harmless and hobbyist pump this into their tank all day long when they enter are through an air stone.
Ammonia is produced by our goldfish as they digest protein in food, it comes out in their waste and is excreted through their gills. It is converted to nitrite, used by algae and plants, or is removed through water changes. Nitrite is produced in nitrification by Nitrosomonas sp. Bacteria in the conversion of ammonia to nitrite. In a mature tank this is immediately picked up by the second part of the nitrification process (Nitrobacter sp.)and converted to nitrate.
Nitrate is a compound that is not toxic to goldfish in small quantities ( <20 ppm). But if it continues to accumulate and the plants are not assimilating it, the sediments in the gravel are not converting to nitrogen gas, or it is not being removed by water changes, you end up with complications like floating goldfish. This is most often not fixable and gradually the fish die.
Simply put Denitrification is a process where facultative bacteria under the right conditions respire nitrate instead of oxygen. This action removes the accumulating/destroys nitrates in the system. Assimilation, is simply uptake of nitrates (and ammonia) by plants (including algae) as fertilizer.
The Goldfish Council TM is now positioned to start a member operated research program. Chris Sotherden and Mark Rausa have collaborated on a web site based registration and data submittal system for members. In a nutshell, this is what we want to do:
PHASE 1: We need 10 to 30 members, each with two tanks to change their water as usual, and measure nitrates weekly. People have various set ups with differences in fish densities, gravel/ no gravel, plants or not, with various filters, etc. We are going to build a matrix with the data and some great volunteers are going to help us build a water quality data bank and find out the differences in our system. This first leg of the program will take a few months and we may have an adjustment or two.
PHASE 2: We are going to ask the researchers (our members) to try some experiments for a few weeks. These changes are likely to be motions like; adding Ceratophylum (hornwort) to your tanks, doing a 50% water change two days in a row once a month, or adding one fish to your tank(s). We will once again monitor nitrates for a couple of months.
PHASE 3: Using our data we are going to adjust and are going to continue our efforts to conserve more water and provide better health for our fish. A subset of our researchers will try a denitrification study using an inexpensive (DIY) system.
Our board asks that you join us on this experiment which asks that you answer the questions about your tanks, and then when you do a water change, measure the nitrates afterwards and report up the data. Most of us have nitrate test kits, they are cheap and any brand is acceptable. Remember, we are trying to improve the hobby for all of us, make our fish live better and healthier lives and conserve water.
If you love the hobby like our board members, we ask you to join us, who knows you might be part of history!Click to Join
Gary Hater, President The Goldfish Council LLC