The wife is out of the house on Monday nights, so I get some bonus fish tank time.  I usually do a thorough glass cleaning, check my levels, do the dosing, take care of any other maintenance issues that need addressed.  However, now that I have this fancy new iPhone it’s easier than ever to take weekly growth shots!  You’ll see the link to the page up there in the navigation – other than that, not much to report for this week.  Added some extra rubble to the tank to try and close up some of the dead space under the over hang.  Still pondering tearing that all out and do a complete rebuild (always the case right?!) but for now I am going to let it sit and grow.  I’ll be sure to post another update next, till then – happy reefing!

I’ve always run a pure RODI top off sump under my tank, and never had problems. I guess on this particular day something inspired the water to evaporate at an unusually high rate – causing the top off to push extra fresh water into the tank and in turn cause the salinity to crash. Several pieces were on the verge of having to be thrown away (including my best piece of Palmer’s Blue Milli)

I quickly set up a station of 5 gallon buckets and began mixing more salt water. Pulling a gallon out of the tank, mixing with higher concentration solution in the bucket, then topping off the tank – checking the SG and repeating. After a couple hours of this exercise, I got the salinity back up to 1.025 and called it a night. The levels appeared stable over night, and this morning I did another water change leaving the salinity safely at 1.026. I’ve detached the top off for the day, and will see how much evaporates throughout the day today.

Moving forward, I guess I’m going to have to add a little salt to my top off solution. As it turns out I’m usually low on CA and MG anyway, so making a batch of reef crystals salt water with a slightly diluted salinity (1.020?) might help keep it more stable. This whole process has been very frustrating to say the least, and now I’m even considering upgrading my control to allow a Specific Gravity probe to help keep this in check. For now, daily manual checks will have to do.