melev

Every three months, I refill the poly tank to the top with RO/DI water. This upright container is rated at 265g, and I have a small float installed to stop filling it at 250g. This provides enough room to add salt to the water.

For the past three years, I've used Sybon Reef Blend salt. It takes two cases of salt to mix up 250g at 1.026sg, so I got four cases of Fritz salt last year and am finally getting around to using it. Right before the cold front hit my area on Sunday, I got the container completely cleaned out and ready for a new batch of saltwater, and turned on my 150gpd Boosted RO/DI system to fill it up.

Incidentally, water in Fort Worth has been very pure this winter. TDS measures 3ppm after the membrane, so the DI resin has lasted a long long time.

Look at how clean it is inside. The water looks blue, because it is freshwater. Once salt is added, the water looks a little more turquoise.

I set up the ladder next to the poly tank, unscrewed the large lid at the top and carried a bag of salt up. With Sybon, it was six 50g bags of salt. When I opened up the box of Fritz salt, it was one large bag. According to the box, 57 lbs worth.

The easiest way to pour the salt in was to place the sack on top of the container and cut open a slit with a utility knife to allow the salt to pour in slowly. It took about five minutes to dump the contents into the RO/DI water. One I opened the second box, that is when I realized I had more salt than the container could hold for the desired salinity needed. Previous boxes were 150g worth, and these are 200g worth.

I decided I needed to split the next bag in half to get the proper amount. Assuming the rule that a 1/2 cup salt equals 1-gallon of water, there must be 100 cups of salt in the single bag. Using a glass pyrex container with measured markings, I scooped out about 45 cups of salt and into another bag. Then using my shipping scale, I measured to salt of each batch. When they were both about 30 lbs each (including the cardboard box the bag was in), I had approximately 100 more gallons of salt mix to add to the 200 gallons' worth in the water already.

Next time I make a batch of saltwater, one case plus this 1/2 case will be the perfect amount, and I still have one more box on hand after that. Plus three boxes of Sybon salt I bought from a club member in January. I should be good until the end of the year.

With all the salt added in the container, I turned on the circulation pump to mix it all up. It ran for about five hours, then I took a sample to measure the results, which I'll explain in a moment.

In the first picture of this blog, you can see some PVC pipes that go down inside the vertical storage tank. They are connected to this manifold of ball valves. One valve pushes water into the poly tank at the very top. The middle valve runs water to the middle of the tank, and the last valve directs water to the bottom of the tank. The purpose of these valves is to keep the circulating saltwater quiet. As saltwater is used up via water changes, the sound of falling water inside the vertical container would intensify. The farther it had to drop, the more thunderous it would be. By adding the longer pipes inside to direct the flow, I'm able to switch heights to limit how far the water falls via circulation. It is always nice and quiet.

You can also spot a small blue handled valve in the picture above. That is the shut off to the poly tank. Once it is full, I close that valve so no additional RO/DI water will flow into the tank. I don't want it topping this off because it would throw off the salinity otherwise.

Here are my test results for the new salt using 1.5 boxes in 250g of water.

Fritz Sea Pro Mix
Temperature: 68° F (the water coming in is cold this time of year)
Salinity: 1.027 sg (Digital Refractometer, calibrated and tested twice)
Alkalinity: 9 dKH (Elos)
Calcium: 450 ppm (Elos)
Magnesium: 1250 ppm (Elos, tested twice)
Phosphate: 0 ppm (Salifert)
Nitrate : 0 ppm (API)

When I opened up the poly tank and looked down inside with a flashlight, it is crystal clear. And I know this sounds silly, but when I smelled the saltwater, the word that popped into my mind was "yummy." That's when you know I'm happy.

And with the test kits out, I tested my reef as well. It was long overdue.

Temperature: 78° F (Apex)
Salinity: 1.025sg (Digital Refractometer)
Alkalinity: 7.5 dKH (Elos)
Calcium: 400 ppm (Elos)
Magnesium: 1300 ppm (Elos)
Phosphate: <.1 ppm (Salifert)
Nitrate: 0 ppm (API)

I knew that PO4 (phosphate) and NO3 (nitrate) were low because the bubble algae in the frag tank has been coming off the rock quite easily lately.

Here's a picture of the reef from Sunday when it was so cold outside.

So in the coming weeks / months, I'll be doing water changes and seeing how the corals respond. I do like the way it mixed up and measured, although I'd like it to have more Magnesium out of the bag. Sybon's Mg was 1600 ppm out of every bag, so I've not had to dose Magnesium since 2010.