[weez1959]

Here we go again with the never ending problems... :P
about 10 days I decided to let my tank go fallow for a month or so because another of my fish was showing signs of ich again!

Anyways the fish are not the problem, they are in 3 separate 10g tanks at 1.018.

The problem is with the DT! I was checking water this morning and my nitrates are almost off the chart! It's at 50! normally it hovered between 10 and 20, now there are no fish and it skyrocketed.

The only thing in the tank now are 5 shrimp, 8-10 hermits and a couple dozen snails. The pod population has exploded since there are no fish and I have a bazillion mysid shrimp swimming around like they own the place.

I'm hardly feeding the tank at all, maybe 1/4 tsp. a day of masago for the shrimp and coral and actually I skipped a couple of days feeding.

I added a pic of an algae bush to show how many pods there are, and while on that subject, anyone know what kind of algae that is?

[leebca]

Your fish will love going back to the DT with all those pods. The pods will learn (all over again) that hiding during the light hours is their best defense!

Pods contribute to waste nitrogen and produce ammonia. So the source of ammonia hasn't gone away.

The denitrification (nitrate to nitrogen and other organics) occurs in the live rock areas where there is a significant reduction of oxygen. The pods can be disturbing these areas, brining in oxygenated water. Also, when coralline covers the rock, it blocks off the areas of low oxygen content, also contributing to the reduced denitrification.

After the fish were removed, did you change or alter anything in the DT?

[weez1959]

I can't believe I didn't think of that! Yes I did change something. I had to dismantle the whole tank to get all the fish out. Will this go back down and how long will it take. Should I stop feeding the shrimp?

[leebca]

I would run the DT just as if the fish were in it (except for feeding the fish, of course). Keep feeding the shrimp and other livestock. Perform normal maintenance, etc.

Did all the rocks go back exactly the way they were before? Are any of them turned or upside down from their original position?

Let everything remain steady.

[weez1959]

I decided since all the fish were out to redecorate so to speak, some were upside down and what not. So I guess that's where the crazy nitrates are from...

[leebca]

Sort of. By alternating the orientation of old rock, it may lose some effectiveness. Watch it to see if its effectiveness returns.

[vaporize]

btw, that is bioypsis hair algae, very difficult to get rid of. Better get that rock out and brush them all off before they spread to other rocks.

[weez1959]

Originally Posted by vaporize

btw, that is bioypsis hair algae, very difficult to get rid of. Better get that rock out and brush them all off before they spread to other rocks.

Yup, it's already gone, not a trace left, hopefully that's the end of it. Too bad, I kinda liked the way it looked!

[tray262]

I've got plently of hair algea that I can share with ya. Anyway's tank looks nice, hope everything in you DT is ok. Good luck.