I received 40 pounds of live base rock from liverocks.com on Wednesday (previous post here
) and started the transition away from bio-balls. I initally removed most of the bio-balls, put most of the live rock in the sump and the remaining live rock in the tank. I also did about a 1/4 - 1/3 water change after putting it all in there.
On Thursday morning I did my first water checks. I'd previously been at 0 ammonia, 0 nitrites, perfect pH and off the chart on nitrates. The new test was 0.25 ammonia (up a notch), up one notch on nitrites on the color card (don't remember the measurement) and my pH went down a couple of notches. I did another 1/4 - 1/3 water change and, having chickened out a little on such a large transition, put 75% of the bio-balls back in. I had removed them into a bucket of their own water and kept them soaking. Since it was less than 24 hours by then, I figured they were still active enough to resume their role until I got over the hump. I shifted more of the sump rock into the tank to make room and repacked it with bio-balls.
Friday morning's water test showed the levels being virtually the same as Thursday... MAYBE trending downward, but too close to call. pH was perfect again (more or less). On the bright side, I was two days into the transition and nothing was skyrocketing. Holding ground seemed good.
I did a 1/3 water change late last night (Friday - technically wee enough hours to be early this morning). I've just checked my levels here at 11:00 AM Saturday morning and I'm:
Ammonia - lower and almost back to 0
Nitrites - 0 again (woohoo!)
pH - Dead on normal at about 8.2
So, it looks like I'm getting over the mini-spike if I'm reading this right. I plan to do another partial water change either tonight or early tomorrow morning to keep ahead of things and hopefully knock out that last bit of ammonia.
I'm certain my nitrates are still off the chart with most of the bio-balls there. I doubt the new rock is offsetting it yet or maybe it never can with the bio-balls being such a factory.
The next step now is to take it slowly on the bio-ball removal. I've ready most people suggesting 20% per week or so. Does this sound reasonable? Should I expect to see little spikes in the process or will the rock start to hold it all on its own by that time?