Should I remove Coil Denitrator now that I have a scrubber

[jcooler]

I just got my ATS online 5 days ago. I have been running a Coil Denitrator for about 2 years now. It has done an excellent job at keeping N at (or near) zero. The reason for the ATS is P removal. I don't have a test kit, but I'm pretty sure it's very high, as I have significant nuisance algae growth on my rocks.

So my question is, should I go ahead and remove the Coil Denitrator? Does the ATS need N to function properly, or will screen grow fine with high P levels alone?

Thoughts?

[Ace25]

In your circumstance, which is not a normal one, I would say yes to removing the coil denitrator... eventually (when you have an established algae screen, and it is not just slime, which is the first part when an ATS is first started, and almost all the slime comes off until finally algae starts to take root). I wouldn't do it yet, I would just feed more than normal for now to add N back to the tank to get the screen going. Yes, N/P and tied together, and will not be able to lower your P if you have 0 N in the tank unless you use a media made for removing phosphates. The algae consumes both N/P and if one is not present it will not consume the other. In your case I would a little GFO or something similar to lower P for now. Just for a month. Ideally you want to have a little of both in the tank, 5-10 nitrates and .03 phosphates. Keep them both at that level and I believe you will have a happy tank.

[jcooler]

Thanks for the quick reply Ace25.
One more thing to add is that I have hardly any green hair algae. Only a few little bitty spots on one or two rocks. It's red hair algae that is the problem. I'm not sure if the red hair grows better with higher P and the green hair needs more N, or if it's just the type of algae that seems to be the more prevalent in my tank.

[jcooler]

Quick update.
I went ahead and stopped using the CD. Figured it might help get the scrubber growing a little faster.
The scrubber has been online for 13 days now. Tomorrow will be the second cleaning. I turned off the CD about 6 days ago. Nitrates are still showing zero, so I guess the immature ATS is already removing any nitrates that have been produced over the last 6 days.
I have mostly brown algae growing on the screen, but a few spots have GHA growing. I really thought it would take longer to start seeing the green, but its looking better than I expected.
It also appears that some the algae is starting to recede, but that could just be my imagination.

[SantaMonica]

Let it grow 14 days this time

[jcooler]

Let it grow 14 days this time

Will do. Thanks for your input. And thanks for showing us all how to save a boat load of cash on filtration systems. :lol:

[jcooler]

Let it grow 14 days this time

On day 17 now. Screen has only been cleaned once, one day 7. Coil denitrator was taken offline on day 6.
The screen now growing some nice, large spots of GHA. Each day, the existing GHA spots get larger, and new ones start to appear. The GHA starts out as light green, but as the spots get thicker, it turns to a darker green.

Nitrates are still holding at zero(ish). Phosphates are unknown ( no test kit).

SM, I think your advice to let the screen grow 14 days was very good. It is really taking off now. I will be cleaning it again on day 21 (12-6-11). I'll post some pics of what it looks like before cleaning.

[jcooler]

I cleaned the screen today (day 21). Had a pretty large amount of GHA on it. Smaller growth was light green. The thicker growth areas were a little darker green.
Leaving for 14 days really did the trick. It allowed it to get a good algae growth base. I suspect that it will be due for cleaning in 7 days this time.
The coil denitrator is still offline, and I took the skimmer off a few days ago. NItrates are still zero.
I had bought a new fish about a week or so ago. It apparently didn't make it, as it is "missing". I'm sure the clean up crew and the the engineer goby took care of the remains. The point to this is that the tank has shown no negative signs as a result of the fish dieing.
So far, the scrubber is doing well on my system. My high hopes are still high. :)

The pics are from day 20. I forgot to take pics before I cleaned it today. The growth from day 20 to day 21 was very noticeable too, so there was a decent amount more GHA on the screen, than what is in the pic. I did, at least, get a pic of the harvested algae.

[kerry]

Real nice growth!!!