General question

[d-maz]

I have a 90g display with a 30g sump that has been running since April. I have probably 150lbs on LR in it, which is 1/3 covered in coraline. I also have plent of coral in there. Nothing huge, but everything from lps to sps. I don`t dose anything unless my levels drop.

I do a 15 gallon water change every other week. My question is, is it normal that my levels rarely ever change? Everytime I test my calcium it almost always around 440 and my dkh is always around 8.5-9.5. My PH is always 8.0 or 8.1.

When I started buying equipment I was looking at calcium reactors, but at this rate I wont need one for years. It just seems odd to me that I rarely ever have to dose anything.

[bertoni]

That is odd, but I wouldn't worry all that much yet. I would get a second opinion on the alkalinity test kit. Alkalinity is the fastest-dropping parameter in most systems.

[d-maz]

When I first started up my dkh was always hovering in the 12 range, but after slowly dropping over the months, it seems to be pretty steady around 9.

[Tbduval]

d-maz,
Just watch your ALk levels closely. My tank did the same thing, then one day it just dropped. Right before the drop in ALK, I notice my coral starting to explode with growth. It was like the tank hit is maturity point and then things starting to grow. HTH!

[kgross]

What salt mix are you using? Some of them are pretty high in Ca and Alk, and for a low demand tank just the water changes can keep them up.

But watch things closely because as the corals grow the calcium and alk demand will increase.

Kim

[d-maz]

Kim- that`s kind of what I figured. I used Reef Crystals, but the last bucket I bought was Tropic Marin. I`ve only done 1 change with the Tropic Marin so far. Stuff in my tank is definately growing, but I haven`t had to add anything in a long time.