Downward spiral

[koldreef]

I've got a 90 gal Reef tank that's been set up for about a year. Never had a problem with anything until recently. I had a powder blue die somewhere which brought my ammonia up to toxic levels (don't remember exact level but it turned xmas tree green) and Nitrate was like 40ish. All my coral seems fine, LPS still all swollen up and eating well; same thing with SPS. Never would guess there is a problem with anything. So I did a small water change (like 20 gal) which helped a little then 3 days later, did a major water change (like 40 gal). I'm using Tropic Marine pro reef salt, and adding Stability to help. Got the ammonia down to about .25ppm and Nitrate gone. Haven't fed tank for a week and now my I have a flasher that looks sick. Mandarin is getting something that looks like ich (not white spots but bumps all over his body) I'm going to do a regular water change today to get rid of the ammonia.
Stock list of fish:
Purple tang
False Perc clown
Purp. fire fish
Blue damsel
Blue Fin Flasher (M) (looks sick)
Carpenter's Flasher (M)
Mystery Wrasse
Spotted Mandarin
Randall's goby
All have been in the tank for over 4 months, no problems. Tank is 90gal Reef w/ at least 150lbs of rock. Various LPS, SPS, softies, 'shrooms. All doing well.
I'm getting really bad diatom algae bloom now too.

 

[azfishgal]

Sounds like your tank went through a cycle, and most live stock can't handle that. Do you have a lfs that will keep your fish for you, while you get your tank under control? Looks like you are going to have to start from the beginning and I would suspect you are going to lose some livestock. Maybe someone else can give more enouraging news, but it looks like you have some work to do. My first instinct is to get the fish out of the DT.

 

[dude23455]

1 fish dying in a 90gal shouldnt be enough to raise your ammonia that much. I've a few fish go in my 90 that I never found, and never had any problems. I would look for some other cause for the ammonia. It does almost sound like your tank is going thru a cycle. If the ammonia was caused by a dead fish, once you removed the dead fish, then the bacteria should convert the ammonia to nitrite then nitrate rather quickly. does that make sense?

 

[koldreef]

The nitrogen cycle makes sense; I think I might have been over feeding a little, then powder blue died, then kole tang died. Got the kole tang out, but Powder blue, had no idea where it went...I just remember when my tank was cycling I had a big diatom (or brown algae) bloom. I just changed cartages on my RO too so I know that's not the cause..
I dunno if my LFS can hold my fish for me I can check mon/tues though...

 

[puffer32]

A tang dieing and never being found can certainly spike your ammonia and cause your tank to cycle. I believe your bioload was to large for a 90 gal to start with, and sounds like you have ich in the tank now (those bumps you said your fish has is ich, just still under the skin) and that was probably due to stress from over crowding. You need to get the fish out and start hypo on them ASAP.

 

[azfishgal]

I agree with Puffer, a Tang could certainly push a 90 gallon over the edge if it dies. How big was he? IMO Tangs should not be in a 90 gallon, just not enough room for them to swim. I would just chalk this up to a lesson learned and do the best you can from here on out. Good luck and I hope you don't lose anymore.