Day 21: Water, water everywhere; Nor any drop to drink.

Sand is on it’s way… somewhere in Illinois and should be here by Friday. The water test kits came today. Can’t move on any “live rock” on craigslist until I can keep it alive in saltwater tested to parameters. I have completed all the work I need to do behind the tank (don’t relish the idea of trying to move a full 900 lb tank to access the back).

So at this point my attention turns to water. While I would prefer to put in the sand first, I can start on mixing the water and filling the tank. It just means the first day the tank will be cloudy with sand. The first batch will be with nothing “live” in the tank (no live rock, corals, fish, etc) so I’ll mix the salt in the tank with the sump pump and power heads. I am filling just as fast as the RO/DI can make water (3 hours so far and 18 of 75 gallons so far) which isn’t fast.

Mixing salt apparently has some harsh effects on water that create the need to let it set for 24 hours and circulate. While I haven’t found the actual chemistry that requires this, I’ve heard various anecdotal versions from the dissolved salt is initially “caustic” and others say that CO2 is created (where did the carbon atom come from in this reaction?) and needs to be “driven off” with a circulation pump. On the other hand there are tons of trace minerals, and calcium carbonate (maybe the carbon atom source?) in the water for the ions to interact with, so who knows what is going on chemically. My suspicion is that neither of these are right and that people just underestimate how fast salt dissolves. This results in hydrometer testing the water with undissolved salt (giving a lower than reality reading) that will subsequently increase the salinity of the water.

To mix water after the initial fill, I have an 18 gallon RubberMaid container that fits under the display tank next to the sump that can function as a place to mix new water. I’ve got a heater I can suspend in it and a small pump to circulate the water. It will also move the mixed water from the mixer to the sump when it is done and the old water has been removed.