Back on topic...I've noticed much better coloration in my SPS since my PO4 started to climb a little. When I was carbon dosing in my last tank, it seemed since nitrate was limited that my PO4 got out of hand and started leaching like mad. This caused a large hair algae outbreak, and gave me an excuse to upgrade. I've decided not to carbon dose in this tank, and keep nitrates between 2-5. I feel it's much easier to keep PO4 in check with nitrate not being limited as well. I'm running GFO and seem to be doing well with PO4 running between .03 - .05 on my Hannah Checker. Since this is a new tank, my Checker was reading 0 for months, and my SPS seemed to lighten up a bit, even with measurable nitrate. When the PO4 climbed, the colors returned. I've always ran 400 watt Radiums on my tanks, and could never understand why my corals were always pale with little growth, even with a 5 hour metal halide photoperiod. Now I'm starting to believe that if you're going to pound your SPS with intense lighting that one of two things must be present:
1. Measurable organics in the water column to help feed corals as they grow and photosynthesize.
2. Lots of supplementing and tweaking if you run low on nutrients or choose to run a full blown ULNS.
I'm inclined to believe that people who run a ULNS don't need as long of a photoperiod either.
Having enough NO3 and PO4 in the water to maximize growth and really bring out colors is obviously a balancing act that every reefkeeper has to figure out on their own. The combination of light, flow and organics is unique to each system. I have only 8 fish in a 200 gallon tank (Achilles Tang, Copperband Butterfly, Bellus Angel, Bipartitus Leopard Wrasse, Yellow Tailed Fiji Blue Devil, Tomato Clown, Dispar Anthias, and a Lyretail Anthias) but I feed them very well instead of getting more fish. This seems to be my tank's stabilization point to keep enough nutrients in the water and still have colorful sticks. There are many who can keep a ULNS successfully with lots of fish, supplements, etc. This has simply proven too much for me to do every day, and I still add a couple drops of Amino Acids and 1 drop per day of Lugol's Solution.
Since we're on the "nutrients" topic, I received 3 very colorful SPS frags today from a reputable online vendor. I tested the water and found nitrates were past the 10ppm reading that my Salifert kit could measure, and PO4 was .14! I realize that any sliming or other wastes that the corals could have released would have affected the small amount of shipping water, yet the tests were done on each of the 3 bags and came out the same. I found it very interesting and contradictory to what we've all believed over the years...or at least me. I think as long as your corals are colorful, growing and hair algae isn't growing everywhere, there may be some benefit in having a great cleanup crew and letting your tank tell you if it needs more or less nutrients.
It's refreshing to know that it can be done without having to strip the water of nutrients. Maybe I can spend more time now looking at the tank instead of fiddling with it.
