Sun, 10/21/2007 - 00:48

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About a month ago, I discovered at MACNA that I was misreading my nitrate test kit for a very long time. I use Salifert kits. Just in case you use the same kit, let me clarify one important step:

After the test is complete (including the 3 minute wait period), if the solution matches 10 or less on the color chart, hold the beaker up and view the color through the side with the color chart behind the beaker. Whatever that result is, divide by 10. So if it looks like 50ppm, it would be 5ppm.

If the solution is higher than 10ppm, look at the beaker from above. If it matches 25, 50, or 100, that is the true measurement.

For a long time, I've been viewing the beaker through the side then dividing by 10 and thinking my results were correct. I was wrong, and my tank's NO3 level was between 50 and 60ppm. I verified this test with a LaMotte kit.

My next decision was how to lower the nitrates. Changing vast amounts of water regularly was one option, but on a system with 330 gallons that would be a huge task and was pretty daunting. For some time I've heard talk of a product called AZNO3, and tried to buy it locally and then again at MACNA. When that didn't work out, I placed an order with Marine Depot that arrived quickly.

After reading the instructions on the bottle as well as the website, I felt I had a plan. Others had written reviews about the product online, and it seemed like 50% of the people were happy and 50% reported all kinds of losses. Rather than just putting blind faith in the product and hoping for the best, I decided to take a slower than recommended approach and keep track of how my reef progressed.

Based on the water volume of my tank (est. 300g on the lower side), it called for 10 drops to be added the first day. Each day thereafter, you double the amount of drops for 6 days. Thus, the recommended daily dose for my tank would be: 10, 20, 40, 80, 160, 320 drops. Instead, I dosed more gradually: 10, 20, 20, 40, 40, 80, 80, 160, 160, 320, & 640 drops. Thereafter, 8ml per 50/60 gallons, or 40 ml per day. Again, using a lesser approach, I'm dosing 30ml per day.

I started dosing the tank on 9/22 and the nitrates were about 60ppm. On 10/19, almost a month later, nitrates are about 15ppm.

Dosing the tank more gradually, more product is used. Marine Depot sells each 8oz bottle for $19, and I've dosed 2.5 bottles so far. Nitrates are down 75% and all of my livestock has been unaffected. Fish, SPS, LPS, softies, invertebrates, anemones, zoanthids, mushrooms, coralline and the maxima clam all seem fine. Macro algae still looks green and healthy in the refugium.

The skimmer is pulling out a massive amount of foam daily, but not a lot of skimmate. The cup is very slimy inside, and it is cleaned out every other day along with the riser. The glass of the tank gets a white dusty accumulation that comes off easily with a cleaning magnet, and no green or brown algae grows on the glass any more. I am seeing a very dark ugly green cyano bacteria on the sandbed, but it hasn't spread into the reef. This is siphoned out when it gets to be too annoying.

During this treatment, I've not run any phosphate removing products. I still run 3 cups of fresh carbon each week in a Phosban Reactor. Phosphate has stayed between 0 and .03 even though I feed just as much as in the past. It seems that AZNO3 reduces or keeps PO4 down. I've done two 55g water changes during the dosing period.

Once nitrates are nearly 0, I'll have to wean the system off this product again, gradually using less each day. I'll update this information in the coming weeks.


The new VorTech Wireless Wave Drivers finally were released, and I have mine hooked up. The conversion from the old driver to the new one was a simple transition, and now the pumps vary the flow internally. I've got them set to Reef Crest mode, which I like. Here's the diagram of how it changes. (Lagoon mode is also displayed in this graph)

This is one of the new drivers.

I'm really glad EcoTech Marine finally got these to market, as everyone has been waiting patiently. Varying speeds allow for more random flow.


Last weekend, I drove up to Oklahoma City to attend the CRASE one-day conference. It was a good event and the next day I was fortunate enough to visit Paul Whitby's beautiful 600g reef before heading back to Fort Worth. Paul's tank is TOTM (Tank of the Month) in Reefkeeping - October 2007.

As soon as I have those pictures edited and added to the site, I'll include a link in my Reef Log.