whatcaneyedo
10-22-2009, 10:26 PM
Not my tank, someone elses.
Back story:
Once a month I give someone a hand with their 3 year old 135gal LPS and softy reef tank by doing a 20gal water change, some cleaning and a bit of water testing. We've been mixing up new Seachem Reef salt to 1.025 (on my refractometer) with RO/DI in a 20gal trash can with a small powerhead and then partially closing off the top by sitting the lid on it. Each month I come over we do a water change then mix up a new batch of saltwater to use next time and just let it sit (so that new saltwater is always on hand in the event of an emergency). We have been doing this the same way for the past year only until now we had been using Instant Ocean.
Yesterday:
I went over to do the water change and tests; the alkalinity was 7.5 dkh, calcium was 400ppm and salinity 1.026. I used to test nitrate and phosphate as well but they have been undetectable for months so I stopped a long time ago. There have been no changes in the way the tank looked or in what has been added for several months.
I noticed some calcium precipitation around the sides of the water change garbage can so I tested the calcium with an Elos kit out of curiosity. 550ppm which is consistent with what I've received before with that salt and those kits. So I do the water change. Immediately all of the coral close and slime up a bit but I dont think too much of it because I had just given everything a quick blast with a powerhead to remove any detritus or sand that had settled on the rocks/coral. I mention that the coral looked a little ****ed off to the owner and then I go home.
This morning:
The tank smells like dead fish and the skimmer is full of dark foul smelling skimmate. The six line wrasse and purple tang are both dead, all of the other fish are gasping. The large colony of anthelia is shriveled, the open brain has a lot of white slime on it and everything else just looks closed.
I rush back over and do a 30gal water change using the water that I've prepared at home for my own system (2 day old 1.025 50/50 IO and Seachem Reef with 2 cups of Randy's Mg mix). I also fill a phosban reactor with carbon and get it running. I shut off the lights to hopefully lessen the stress on the remaining fish.
Everything still looks pretty upset and we're mixing up some new saltwater for another water change tomorrow.
Before the water change:
26ºC
1.025 (with their hydrometer)
Ca 400
Alk 7
Mg 1100
What I think went wrong:
We've been letting new saltwater sit for a month before each water change un-oxygenated in a nearly sealed container with a small powerhead. The seachem reef salt probably had a very low pH by the time it was used. The low pH shock likely caused the anthelia colony to crash which began the tank crash.
In future:
We're going to mix saltwater up one week (instead of one month) in advance with a larger pump, leave the top open and possibly add an air stone. I'll begin supplying my own supplements to bring the water parameters up to higher levels. Targets will be Ca 420ppm, Alk 9dkh, Mg 1400ppm.
Back story:
Once a month I give someone a hand with their 3 year old 135gal LPS and softy reef tank by doing a 20gal water change, some cleaning and a bit of water testing. We've been mixing up new Seachem Reef salt to 1.025 (on my refractometer) with RO/DI in a 20gal trash can with a small powerhead and then partially closing off the top by sitting the lid on it. Each month I come over we do a water change then mix up a new batch of saltwater to use next time and just let it sit (so that new saltwater is always on hand in the event of an emergency). We have been doing this the same way for the past year only until now we had been using Instant Ocean.
Yesterday:
I went over to do the water change and tests; the alkalinity was 7.5 dkh, calcium was 400ppm and salinity 1.026. I used to test nitrate and phosphate as well but they have been undetectable for months so I stopped a long time ago. There have been no changes in the way the tank looked or in what has been added for several months.
I noticed some calcium precipitation around the sides of the water change garbage can so I tested the calcium with an Elos kit out of curiosity. 550ppm which is consistent with what I've received before with that salt and those kits. So I do the water change. Immediately all of the coral close and slime up a bit but I dont think too much of it because I had just given everything a quick blast with a powerhead to remove any detritus or sand that had settled on the rocks/coral. I mention that the coral looked a little ****ed off to the owner and then I go home.
This morning:
The tank smells like dead fish and the skimmer is full of dark foul smelling skimmate. The six line wrasse and purple tang are both dead, all of the other fish are gasping. The large colony of anthelia is shriveled, the open brain has a lot of white slime on it and everything else just looks closed.
I rush back over and do a 30gal water change using the water that I've prepared at home for my own system (2 day old 1.025 50/50 IO and Seachem Reef with 2 cups of Randy's Mg mix). I also fill a phosban reactor with carbon and get it running. I shut off the lights to hopefully lessen the stress on the remaining fish.
Everything still looks pretty upset and we're mixing up some new saltwater for another water change tomorrow.
Before the water change:
26ºC
1.025 (with their hydrometer)
Ca 400
Alk 7
Mg 1100
What I think went wrong:
We've been letting new saltwater sit for a month before each water change un-oxygenated in a nearly sealed container with a small powerhead. The seachem reef salt probably had a very low pH by the time it was used. The low pH shock likely caused the anthelia colony to crash which began the tank crash.
In future:
We're going to mix saltwater up one week (instead of one month) in advance with a larger pump, leave the top open and possibly add an air stone. I'll begin supplying my own supplements to bring the water parameters up to higher levels. Targets will be Ca 420ppm, Alk 9dkh, Mg 1400ppm.