nitrates going up

[danno]

For some reason my false perc died. Everything was fine untill then as far as I know. All fish were/are active, inverts active, mushrooms reproducing/splitting, coraline growing everywhere.
But now my nitrates are at 40 (used to be in the 5 range)! Could this be due to the dead body? I have looked and looked but I can not find Mr. Clown anywhere. My brittle star was fatter, but I recently had fed him. Or, is it possible that maybe he even killed the perc? All of my other levels are at zero. I did replace my crushed coral 3 weeks ago over a 2 week period with live sand. Is this a cycle happening.
thanks for any help
other specs:
29 gal
Protien Skimmer
3 inch, 40lbs, sand bed (could this be the problem?)
Hang on filter
3 juvinile chromis
1 juvinile clown
25 lbs live rock
condy
brittle star
small halmedia
misc plant
small red mushroom colony
2 shrimp (pepermint and skunk)
other cleaners

 

[baondayko]

Not sure I can help, but I do have a question. I would like to replace my CC with LS. How did you do this over a two-week period. Any helpful hints?
The missing clown could definitely be causing your ammonia and then nitrates to spike.
I also have a brittle star, what do you feed it?
Thanks
Brock

 

[danno]

When I converted I vacumed the CC well (to minimize debris). Then I scooped out half of the CC and replaced it with live sand.
When I added the sand I scooped it out of the bag with a cup and poured it onto the floor of the tank with the cup as close to the bottom as possible. The debris settled in less than 24 hours. I let it sit half and half like that for a while 10-14 days and then repeated. Tank has never looked more alive. But definatley Vacume the CC that you are going to take out very well, it is surisingly dirty under there.
I hand feed the brittle star a single vitamin fortified krill once a week. I do the same for my condy and arrow crab. A single shrimp keeps the arrow crab happy/busy/full for 2 days some times more. This in return keeps him from harassing the rest of the tank which he hardly ever does.

 

[richard rendos]

The nitrates could go up from the death of a fish, but nitrates will go up without fish death...just part of the nitrogen cycle. How often do you do partail water changes? Also, have you checked other water parameters?(pH, ammonia, nitrites, calcium, etc.)