Pale Fish -> Dead Fish

[desx2501]

Hi,
I'm new to the hobby, so is my aquarium. Here are infos :
It's a 55g tank, and my only equipment are: a heater, a tetra whisper ex70 filter, 2 lights (not the coral ones). I do NOT have a skimmer yet, was planning to buy one in about a month since the guy at the aquarium store told me I would be fine without one for about 3 months if I don't have many fishes.
It has some live rocks in it, with some coralline algae.
The pH is around 8.1-8.3, the salinity is fine with 1.022 specific units, the ammonia, Nitrite/Nitrate levels are so low they don't read in the tests. I'm past the ammonia/nitrite/nitrate spike.

I've had 7 marine hermit crabs and 1 snail in it for about 3 weeks.
I feed them 2-3 times daily, then I added 2 fish one week ago : one clown fish and a coral beauty.

The Coral beauty has been shy since she's in there, always hidden in the liverocks. Yesterday, we've noticed that the coral beauty was a bit pale.

I just found the coral beauty dead at the bottom of the tank, on the side, with an hermit crab on her. I don't think the hermit killed her, but I have no clues what might have caused her to die.

I would like your input so I can make sure the same faith doesn't happen to the clown fish. Any ideas?

Thanks,
Xavier

[Ethan Music]

depending on the hermit crab size you would be suprised what they can do but im with you it probably did not kill it. He was just doing its job saw a dead fish and said ahh lunch. Also I would not wait to long to get a skimmer its one of the most important parts in a saltwater tank. Most fish are usually shy the first few days or week atleast. Other than that can't help you much without being there or more information like behavior or chemical tests.

[desx2501]

without being there or more information like behavior or chemical tests

Since I don't know much, what kind of chemical tests would you do?
I checked pH, Ammonia, Nitrite/Nitrate, Salinity and Carbonate Hardness and they seemed fine.

As for the behavior, the Coral Beauty was always hiding in the live rocks, barely coming out to get a snack, but not that much either, like she didn't have an appetite. What we are feeding them is "Nutrafin Max" and some "Brine Shrimps", which we unfreeze with a little water taken in the tank, like the guy who sold us that told us to do.

Could the feeding have been improper?
If they were over/under feed, how would they have behaved?

[desx2501]

Could it have been oxygen deprivation? I don't have an air pump in the tank, and since the Coral Beauty was always hidden at the bottom of the tank, maybe the filter wasn't sufficient for it?

[Ethan Music]

could have been was his gills moving rather fast if so could have been lack of oxygen do you have any power heads in your tank to circulate your water? If not you should look into getting some power heads in the tank to move the water around. And as far as air pumps go any bubbles in a saltwater tank are bad. The air stones if thats what your talking about that use an air pump to blow bubbles are bad for saltwater aquariums. We use power heads to create flow and agitate the water. Some brands are vortech, tunze, koralia.

I've never had a fish that never ate and ended up dieing thank god guess im lucky. Depending on the fish mysis, black worms, squid or some people use a garlic supplement to put on the food to get the fish interested. My exsperince after 3-5 days or maybe longer without eating their instincts kick in and start to eat slowly gradually. Personally I don't think fish can die from over eating they can become over weight and less active but dought he over ate himself. With that frozen food you do have to be careful if its not unfrozen all the way they can inhell more than they can digest in one bite my friends clown had a close call from this once he had a bigger piece than what he could get down and was pretty much choking to death lucky he was able to get it out.