My bad. I always assume people can read my mind!! haha!
Tank: 120G inwall Modified Berlin w/30G sump. Moderately deep sand bed 3"-3.5" of mixed oolitic and standard grain aragonite. Lighting is new 2 x 250W 10K Sunburst. Skimming is performed by an oversized Precision Marine CV626 venturi type skimmer. I run a calcium reactor, dose Iodine once per week and dose Kalk slurry once per week. I run carbon passively for about one week per month then remove. Return pump is a Mag 36 (I wanted the ability to add an additional biofilter/sump). I have nice strong random currents with this setup. I have about 100 lbs. of LR and a nice open design.
I have exchanged about 250 gallons of water over the past 2 months under different schedules to see if there is difference in making fewer massive changes or daily small changes. I am changing 5 gallons daily now and always siphon out the cyano and detritus and silt/mulm from the rock work.
Parameters are as follows: Nitrate = not measurable, PO4 = not measurable, Ca = 380, dKH = 9, PH = 8.1, temp = 80
Fish load: Small-med Powder Brown tang, Small-med yellow tang, six line wrasse, pymgy angel, maroon clown
Moderately stock mixed garden reef. SPS, LPS, Leathers, two clams. All corals except one or two are two+ years old.
System was transferred into the wall in May. Most livestock, sand, rock has been together for about 5 years.
I feed every other day and small quant of mysis and nori. Occasionally I switch foods for variety.
There you have it. Any ideas on probelm resolution. Sulfur reactor, KNO3, lactose, add a biofilter, aerobic sand bed??????????
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