So I have a 55 gal. Reef tank ehiem pro 3 I've been running carbon since day one it's about 6 mo old I've slowly added fish I was up to 11 fish 20 snails 20 crabs two feather dusters and one soft coral coral was just added a month ago or so and last week on Monday I was haveing a lot of algae growth red and brown on all the live rock about 40 pounds worth and the inside of the glass I couldn't clean it fast enough water tested fine with the basic test kit I have I added pristine organic waste management chemical to see if that would help and about a week and a half later out of no where I woke up in the morning and lost half my fish and lost all but one watchman goby within 24 hrs of that I took a water sample and rushed it to my local fish store after a 25% water change and a test at home numbers were right on they told me to stop using carbon in my filter and switch to phoslock I did that and had to leave town for 3 days I came back to the dirtiest my tank has ever been since then I have done a 75% water change and a 25% and added carbon back to the filter along with the phoslock I removed some live rock so I could clean the seaweed like algae off the substrate everything seems ok for now but it's only been a couple days since the big water change note all snails crabs feather dusters one watchman goby and the soft coral are alive and well am I on the right track did I really feed my fish to death I have a phosphate test kit on its way and a protein skimmer looking for tips or if anyone can tell me where I went wrong how I lost all my fish in a 48 hr period
Lost all fish in 48 hrs
- Thread starter CSKP0708
- Start date
It's called a tank crash. The biosystem (rock/sand) couldn't process fast enough, and the addition of a 'help' dose may have actually made it worse. The thing you do when you see the chemistry go south is to move all healthy critters and corals to a bare glass clean tank with uncycled water, and just keep changing the filter. Taking the load off CAN help the biosystem to right itself and catch up---and if the tank goes all the way down, at least your fish and corals can stay alive. THere's an extensive file on setting up , up among the files stuck up top of this forum, and a thorough read may help you avoid this situation. You didn't have as strong a system as you needed for that many fish. I do not know why the store advised Phoslock, but the carbon MIGHT have helped. Removing live rock worsened the situation. The red/brown was likely not algae, and not due to phosphate overload, but a bacterial sheet called cyanobacteria, and it is not that dangerous, left to itself: looks awful, but it's kind of a periodic natural occurence in some tanks---comes and goes. THere are ways to get rid of it, but the skimmer is a real good step in that direction. Good you could save some critters. Keep them in clean water and let that tank recover.
11 fish in a 55 gallon tank is a LOT of bioload. The fact that you woke up in the morning with half your fish dead makes me think you may have had an oxygen-deprivation event.
Basically, when a tank is near it's oxygen carrying capacity, a death (or even a lot of organic decay, such as dying algae), can cause a bacterial bloom. This bacterial bloom consumes more oxygen, causing more fish to suffocate and die, causing more bacteria, cause more death, etc. This typically happens when the lights are off and the surface algae in the tank is no longer photosynthesizing (creating oxygen), but respiring (consuming oxygen).
The way to prevent an oxygen-deprivation event is to ensure the tank has sufficient water-surface agitation (to facilitate maximum oxygen exchange), always remove dead or decaying matter before lights out (including uneaten food, if you feed larger items), and staying below the tank's maximum bioload.
Good luck,
Kevin
Basically, when a tank is near it's oxygen carrying capacity, a death (or even a lot of organic decay, such as dying algae), can cause a bacterial bloom. This bacterial bloom consumes more oxygen, causing more fish to suffocate and die, causing more bacteria, cause more death, etc. This typically happens when the lights are off and the surface algae in the tank is no longer photosynthesizing (creating oxygen), but respiring (consuming oxygen).
The way to prevent an oxygen-deprivation event is to ensure the tank has sufficient water-surface agitation (to facilitate maximum oxygen exchange), always remove dead or decaying matter before lights out (including uneaten food, if you feed larger items), and staying below the tank's maximum bioload.
Good luck,
Kevin
Tripod1404
Active member
I agree, I dont have that many fish in a tank ~2.5 times larger. That is way too much unless you have another 55 gallon sump or something.
Like [MENTION=1075]Anemone[/MENTION] said, scarping the algae probably caused a bacterial bloom (due to nutrient released from dead algae) which consumed oxygen.
Plus one on this.
"11 fish in a 55 gallon tank is a LOT of bioload. The fact that you woke up in the morning with half your fish dead makes me think you may have had an oxygen-deprivation event."
Ammonia is the worst enemy of a reef tank. If you reboot just let the tank cycle for 3 months with just live rock/sand and the inverts. I would not add more than 7 fish to that tank. It's just is too small to process all that bacteria/waste. Corals are fine when things are on point. Sorry this happened to you. Happy that you shared this however so others can learn. Don't give up. Just scale everything back and watch everything thrive.
"11 fish in a 55 gallon tank is a LOT of bioload. The fact that you woke up in the morning with half your fish dead makes me think you may have had an oxygen-deprivation event."
Ammonia is the worst enemy of a reef tank. If you reboot just let the tank cycle for 3 months with just live rock/sand and the inverts. I would not add more than 7 fish to that tank. It's just is too small to process all that bacteria/waste. Corals are fine when things are on point. Sorry this happened to you. Happy that you shared this however so others can learn. Don't give up. Just scale everything back and watch everything thrive.
AlSimmons
New member
I may have missed it in the original post, but what was the Nitrate reading before the crash? IME this is an indicator. The tank can't keep up with the Bioload so the Nitrates go sky high trying to process all the "crap" within it. After awhile the rug is basically pulled out from under the tank and a crash is inevitable... Back to square one.
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Excellent point AISimmons. Great indicator as well.
