All my fish are dieing and i dont know why

All my fish died thursday in my 55g marine tank. however none of my snails, crabs, shrimp, polyps, or coralline algae have died and all seem to be doing fine. i have a few ideas to what may have happened but ill tell you everything i can to help diagnose the problem so i can restore my tank. My tank has 35lbs of live rock with some coralline and polyps growing on them (the polyps are the only corals in there and theres only about 5 baby ones). It has roughly 60 lbs of live sand, a 55g power filter, a 1300 gph powerhead, and a venturi skimmer with a 225 gph powerhead. The lighting is 215 watts of 50/50 actinic. my tank was stocked with 1 clarkii clownfish, 1 yellow tang, 1 blue tang, (Im planning on setting up a 125 gallon tank when the tangs get bigger but they were only about 1" so i think they were fine in the 55g for now) 1 humphead bannerfish, 2 false percula clownfish, 1 four striped damsel, 1 peppermint shrimp, 10 cerith snails, 20 blue leg hermit crabs, and 2 turbo snails. The tank has been running since early august. Here are a few problems that i have with my tank that i am aware needs to be taken care of.

1. I was unaware that you need to add trace elements to your tank when running a protein skimmer and i was not doing so

2. The clarkii liked to dig in the sand next to the filter so the filter got clogged without me knowing due to the sand getting sucked up

3. I have a really crappy protein skimmer that produced some microbubbles into the tank

let me know what you guys think could have caused my fish to die thank you so much

 

Krakaslap

1st - trace elements , if your doing water changes, them IMO you do not need to add those , and certainly not for the benefit of fish (some with more corals may choose to do so)

IMO you do have a tank that was stocked with fish on the heavy side - the tangs may have been small but they eat a lot and produce a lot of waste

if the filter was blocked and provided the main source of your bio filtration in this heavily stocked tank, then its possible that the ammonia / Nitrite levels spiked, and then you get a domino effect, one fish dies, the decaying fish increases those levels and the next fish dies

at the same time if the filter is not working and it was the main source of water movement in the tank, your dissolved oxygen levels could have dropped and that combined with the nutrient issue could have sparked off the collapse of your system

Steve

 

How was your ammonia, nitrates, etc? That seems like way too many fish added within a couple months. They were probably going through cycles constantly.

 

To add to what Steve mentioned, I do believe you don't have enough rock for a 55. We calculate 1 and some even put 2 pounds of live rock per gallon of total water volume for a good beneficial bacteria colonization. This would help keep your water cleaner. Do you have a sump? Have you tried adding chaetomorpha (macroalgae) to it? It will process a lot of your nitrates.

 

Hi,

Sorry to hear about the recent crash of your system.

If you are going to give it another go, and I hope you are, it is a good to bounce ideas for future purchases off member of this forum. Get as many opinions as you can and garner what is relevent to your situtation.

Let us know what we can do to assist you.

 

I hadn't noticed this. There definitely needs to be more rock added. I have about 70 pounds in my 29, granted half of it isnt as porous. I don't have a sump either but I made it all look good (imo) with plenty of room for the fish to swim around it.

 

i was told that if i had 1lb per gallon of live sand that i only had to put 1/2lbs of rock in there, but its very likely that that isnt true but i assumed it would be fine with the bio filter as well. I do not have a sump nor macro algae. i cant believe i forgot to put all my test results on my post so here they are (FYI i have an API saltwater test kit and an API reef masters test kit)

ph 8.2
Ammonia 0
Nitrite 0
Nitrate 5
Phosphate 0
Carbonate Hardness 10 degrees dkh or 179 ppm KH
Calcium 440 mg/L (ppm)

P.S. these were the test results the day that all my fish died and i just tested them again and its identical except nitrate is 0 due to a 50% water change