Fish Dying - Help!

ericlilly5

New Member
It seems that I cannot keep my fish alive for more than a few days. The tank is a few months old with the following characteristics: 75 gallons, cascade canister filter, two circulation pumps, live sand and live rock, SG of 1.023 and water temp of 78 using real ocean water. Using an API test kit, the pH is 8.0, ammonia is 0 ppm, nitrite is 0 ppm and nitrate is 5 ppm. The tank does not receive direct sunlight and is located in a living room with moderate traffic but within sight of the front door.

I started the tank with damsels and had no problem with them at all. I moved the damsels to a tank for my son and added a naso tang, fairy wrasse and threadfin butterfly from my local fish store. The nano tang died after two days and the other two died after one week. The naso tang was most likely too small for the tang but appeared to have spots meeting the characteristics ick. The other two seemed great until one morning the threadfin had died and the wrasse was losing color and lethargic until it died later that day. Neither had spots when they died. I was unaware of the drip method for acclimation and was worried that perhaps I did not acclimate them properly.

I cleaned my canister filter and did a 50% water change with real ocean water and made sure that the SG, pH, ammonia, nitrite and nitrate were ok which they were. I ordered fish online this time and got two clownfish, a yellow tang, a blue hippo tang and another threadfin butterfly. I acclimated the fish for 2-3 hours using the drip method. The threadfin appeared DOA but after acclimation and some time in the tank seems to have snapped out of it. It died two days later. I checked the water quality and everything was standard. The two tangs looked lethargic and had some color fading before dying on the third day. The blue hippo appeared to have been trying to gasp for air from the top of the tank toward the end. While the blue hippo was gasping for air, one of the clownfish just suddenly died. It had been swimming in front of the circulation pump for most of the day. The remaining clownfish seems perfectly fine, for now.

Any comments or suggestions would be appreciated! I have been reading everything I can find but I am running out of ideas and growing increasingly frustrated. Am I stressing the fish somehow?
 

silverado61

Well-Known Member
Repost this in the "fish disease & treatment forum" and Beth, our medical expert, can help better than anyone else here. But, I can tell you that you added way too may fish at one time. Did you quarantine them before adding them to the display?
Last, all the fish choices, with the acception of the clowns, are too big for a 75 gallon. At least one, if not all, of those factors probably played a part in the problem your having.

Just a thought.
 

jay0705

Well-Known Member
Both tangs are too big for a 75. The clown and wrasse would have been ok. Your tank isnt very mature , so it cant handle a more than 1-2 fish a month.
That said something is off , u have no life in it rt now?
 

ericlilly5

New Member
Thanks for your input, I have one clown left and sounds like I received some bad advice from the LFS. Where is the best location to determine the minimum tank size? It seems like everyone website has different recommendations but on all the fish I just lost they were within the minimum recommendations shown in the description.
 

geridoc

Well-Known Member
You mentioned that you were using natural seawater. Where did it come from? Water taken from close onshore is frequently contaminated, while studies have shown that the seawater you buy is usually collected well offshore, but may be contaminated with fuel from the very boat doing the collection. While using natural seawater sounds nice, I prefer the well controlled composition of salt water I make myself from a commercial mix.
 

2quills

Well-Known Member
Tangs need plenty of oxygen in the water column. The more flow you have from you pumps/powerheads the better-it helps promote gas exchange.

What size is your canister and powerheads? You should be seeing some good ripples/water movement on the surface.
 

ericlilly5

New Member
I have a cascade 1200 (315 GPH) with two powerheads (700 GPH EA) with one on each side of the tank. There are ripples on top of the water. Would the height of the water (about 1 in from top) be an issue? The top of the tank is essentially sealed except for the area for the filter input and output.

Looking from the bottom, there appears to be a slight film on the top of the water. I did not notice this before so I turned by canister output upward to produce more ripples on the top of the water.
 
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2quills

Well-Known Member
Your flow rates sound good but typically we stay away from sealing the tops of the tanks in a marine system. It cuts off the gas exchange and you get an excess build up of co2 in the water column. Sensitive fishes like tangs will be the first to struggle with it. Clown fishes are harder to kill and can survive longer in less than ideal conditions.

Keep an eye on temperature fluctuations with your tank receiving natural sunlight. A swing of a couple of degrees throughout the day is fine. But stay away from large swings if possible.

FYI, I don't think that Natural Sea Water is actually natural. I think that's just what they named it lol. But it seems fine. I've seen other people using it without issue.
 

jay0705

Well-Known Member
U want more open space on top for gas exchange. As far as tank size, ask here we dont sell fish lol
 

ericlilly5

New Member
Thanks for all your comments, much appreciated! I am going to remove the plastic extensions from the lid which will leave the back two inches open for ventilation. I will also lower the water level to help with the gas exchange.

I will definitely do more research before adding fish again!
 

geridoc

Well-Known Member
Removing the plastic extensions on the rear of the lid may not be sufficient. Most of us get rid of the lid entirely and prevent jumping by covering the tank with eggcrate, which can be gotten at any big box hardware store.
 

flower

Well-Known Member
The RO came from the LFS.
Hi...I'm confused ( not hard to do)

You said you use "natural seawater"...but then you say RO is from the LFS?

Also, this site sells pocket guides for fish and inverts, the right size tank for each specimen is in the info they provide... Those books are worth their weight in gold, and that way you won't have to rely on web sites or the LFS for the right fish for your size tank. It provides a picture of each critter and their care, they are really good books to have on hand when you go looking for critters for your tank.
 

RobP

Member
I too would lose the tank lid all together and start using the made saltwater from the LFS just to rule out them getting a bad batch of real sea water. Also, this site has an awesome guide on acclimating fish. This is a must since doing it wrong will overly stress the fish and they will not live long at all. Also just my 2 cents but I don't think canister filters should be used on saltwater tanks. If you have the proper live rock to support the live stock cycle you shouldn't need it. I have a 55 gallon tank with about 65 pounds of live rock and my water is perfect. Good luck either way though.
 

silverado61

Well-Known Member
You could save a good chunk of money by mixing your own saltwater. All it takes is a new 33g Rubbermaid garbage can labeled "Fish Only", a power head, sea salt or reef crystals, RO water from Walmart, a heater, and a refractometer. Keep the lid on the can and the water will store forever. Put the can on wheels so you can move it around. There's a one time investment but it'll pay for itself in the savings you'll have.
 
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