I inadvertently killed all of my invertebrates. 4 weeks ago I purchased a complete established reef system, a 30 gallon innovative marine tank with a kenya tree colony. I was a freshwater keeper for many years keeping mainly geophagus and other south american fish. This is my first time keeping a reef. After the move ammonia did not spike, the biological colony didn't seem to skip a beat. I test my perimeters weekly and I haven't observed any shift out of the norm for my water. I have been doing weekly 25 percent water changes, mixing my saltwater over night, using a heater, testing the PH and salinity (obviously) before adding the batch to my tank, doing everything I can to avoid disaster. The current perimeters are as follows:
0.023 specific gravity
75 degrees Fahrenheit
I think my flow is medium, I have a hydor 425 gph
nano powerhead and the tank is 36 inches wide.
I have a kessil a150we 6000K on the tank for 6 hours a day.
Everything was going fine until last Saturday, I did my usual 25 percent water change in the morning, and the corals just didn't open up all day, I thought maybe they were being grumpy about the procedure. However, they never opened back up. The next day my fish, a clownfish (CB), a lemon damsel (WC
), and a sixline wrasse (WC
), started tp exhibit mild signs of aggression which I had not seen before. My longspine urchin began dropping spines. I sensed something was very wrong. Up until now, and this is my theory for what my mistake was, I have been using water from my RO
unit, but I wasn't re-mineralizing the water. I believe I poisoned my entire tank with water which was too soft. I immediately did a 50 percent water change using de-chorinated tap water, which is fairly hard (I live in chicago), the fish seem less agitated now, but all the coral is dying, some are turning black, which I promptly remove, the urchin is still dropping spines, suffering, slowly dying in the corner of the tank. My remineralizer is still in the mail, it was delayed somehow due to covid-19, I also ordered a hardness test kit which I realized all too late I was missing from my test arsenal, it should be here in a day or two. I feel like I am trapped and have to watch these poor animals suffer under my care, I am so upset and have been taking it really hard. Do you think my hunch is correct? I will know for sure just how soft the water is when I receive my test kit, and will follow up with those numbers. Could this be anything else? Do I need to raise the salinity? Do I need to somehow add calcium? Do I need more flow for the coral? Is there any chance of recovery? I really need guidance. I feel like a complete failure to my animals. Please let me know what you would do from here. Thank you in advance.