Tank Chemistry and Nutrient Control Help Please

SDReefer · Dec 9, 2017

Hello everyone,
My greenhouse tank has been set up since July of this year and I would like to make it into a full reef tank. However, the hardy SPS corals I have put in such as Birdsnest and Pocillipora have all STNd and many of the soft coral frags have started to melt. I assume that something is really off with my tank's reef chemistry.

Also, I would like to know what the best method of nutrient control would be for the tank. I was thinking of doing a chaeto reactor or algae scrubber, but the problem is that there can't be any lights on during nighttime as not to bother the neighbors. Please suggest some new methods or maybe some ways to make it so that there is no light emmitted at night. Maybe I could put the reactor/algae scrubber in a box and cut holes for the input and output? Any suggestions are appreciated.

Tank Parameters

Temp - 70 - 79 degrees F depending on time of day and season; no more than 5 degree swing per day
Salinity - 36ppm / 1.027 sg
Nitrate - 25 ppm (API)
Mg - 1140 ppm (Salifert)
Calcium - 500 ppm (API)
Alkalinity - 4.8 dKH / 1.70 meq/L (Salifert)
Nitrite - 0 ppm (strips)

Please also suggest any test kits that I should upgrade to. On hand, I have ESV Alk and Calcium, as well as Kent Magnesium.

Pictures

The Complete Setup

The "Display" Section

The "Refugium" Section

Randy Holmes-Farley · Dec 9, 2017

The alkalinity is too low and that may be part of the hard coral issue. Magnesium is also low, but less likely to be the immediate problem.

Organic carbon dosing required no light and can be a good method. Algae growth can also be done during the day.