I have a fully cycled saltwater aqarium of 75 gallons. It is a fish only tank. I have a canister filter (mechanical and bio setup) and a wet dry trickle firster that hangs in the back as well. The tank took about 6 weeks to fully cycle. The amonia is constant at 0ppm the nitrites 0ppm the nitrated are currently at 60pm and slowly dropping Salinaty at almost 023, ph constant at 8.2. I feed my fish very sparsly (freeze dried food. I have brown algae starting to grow on the substrate (crushed coral sand). I have a large air pump with a large air wand attached (I run it very high for max oxygenation and effect.
My problem is that through the cycling process the only fish that survived is my small niger trigger (he is doing excellant and very active and healthy). But when ever I add ANY new fish (usually 2 at a time) THey do great fot the first 2 days then on day 3 they start to show signs of stress (blotchy color, breathing very hard, loss of appetite). And by the nd of day 4 they die. I have tried several different types of fish (typically very hardy fish). Does not see to matter. However through it all my trigger seems completely fine. I am guessing its shock? I dont know of any disease that can kill a fish in 4 days. I have evn tried getting them from different retail shops. Currently going on day 4 for the newest fish are a Maroon clown and panther grouper. Both are already breathing hard and seem near death. No noticeable spots or fungus. But again the trigger shows no ill effects.

Whats next?
Can I save them?
Besides using the drip method nest time to acclimate and probably only introducing 1 at a time.

You pose an interesting problem. The fact that the trigger is fine throughout the difficulties you're having lead me to believe that the fish itself may be the problem. Triggers are aggressive and it could be harassing the new additions to it's tank. The fact that it's taking so long to loose the new arrivals indicates to me that they may be dying from exhaustion.

I'd remove the trigger, do some research on which fish I want (compatibility with others, size, etc.), do a large water change to reduce nitrates, and possibly add a Poly Bio Pad to my filtration.

Fish only tanks are fine if that's what you like but you need to plan for either frequent large water changes or a denitrater to keep nitrate in check. You might also want to consider heavily planting the tank with macroalgae. Your wet/dry is very effective in reducing ammonia and nitrite but the end result is production of significant nitrates. Macro algae usually thrives under this condition.

Good luck.

__________________
Doc

Dr Hank's 200 gallon Reef Tank
http://www.aquariumforum.com/f46/drhanks-tank-3440.html

Well during the cycle the fish are exposed to Amonia then the Nitrite which can/will kill them, you can cycle a tank without fish, you can use food and leave it to decay or buy Live Sand my tank cycled in just 2 weeks with Live Sand.

Briwn algae in most cases will pass I have had a few outbreaks here and there, but Brown Algae needs light and Nitrate so if you have a lot of both you are just feeding it.

Just point a Powerhead/Wavemaker at the surface instead, some folks say the Air Bubbles can harm your fish, I never used an air pump in my tank so I couldn't really confirm this.

And as the other post says your Trigger may be killing them, how big was the fish you added, if they are pretty small the Trigger may just see this as a meal, you could always get your LFS to test your water just to double check it, if teh trigger is living but it will prob be fine.

niger is non-agressive towards and even disinterested in most. Here is a laundry list of all the fis that have died (post tank cycling) Miniautus grouper, Clown trigger (which was slightly bigger than the niger and was much more agressive) Volitan lion (trigger avoided him all together), Tomato clown, Coral beauty angel, Sailfin Tang (much larger than trigger), Imperator Angel, Dwarf Lion, Panther grouper, Maroon Clown (which actually hung out with and even slept with trigger..best buds). All are very active and hungry on days oen and two..then appetite goes away on days three and fore. Non-had any sign of Ich or disease. However on day 3 all always started havy breathy and faded colors..even niger trigger showend some color fading but he never seems to be in full distress like the others.

I can turn down the bubbles if perhaps maybe the bubbles are causing some kind of resperation problems?? Never heard of that. My logic was always "more bubbles = more tension disruption of the water = more oxygen. But maybe since the niger trigger has a smaller mouth and smaller slits (gil openings) he is less bothered by this? He in fact tends to play in the wall of bubbles at times.

How is he able to adapt to this condition but no other fish. Only one lasted more than 4 days and that was my Volitan lion he lasted 12 days and seemed happy and active untill the 10th day.

I was very sucessfull maintiaing this same tank 16+ years ago and was able to grow any and all fish i had in the tank to very good sizes (rarely had any loses (except for one that were too small and my groupers eating them). But then I had to move and had no room for the tank so its been in storage for 16 years untill now that I finally have room for it once again.

Triggers are lovely but get quite large and are messy fish. If you want to keep him check out the tank size you need. I would have thought your tank was about right for him on his own.

As I said with the bubbles, I never used an airstone but if you look over the net you will find folks who say it does and other who says it doesn't matter, I was throwing an idea in, I had a trigger and it was aggresive not very aggresive but still aggresive to my other fish except a Picaso I had in with it.

As DrHank said you have an intresting problem, if the water was bad then the trigger would go also so you can maybe rule that out, when you put new fish in do they hide a lot this can be a sign they are getting bullied by the trigger, If possible you could remove the trigger from the tank and add a new fish and see how it goes, if you add a fish and it is fine bring the trigger back if the new fish starts to die after this you can start to look at the trigger as being the problem.

well I think you have all hit on several smaller pieces to this and if all put together they creat a good hypthosys (spelling?).

problem 1) too many bubbls+ not enough water surface tension disruption= not enough oxygen + possible negative bio-effects.

solution to 1) turned down nearly off bubble wand+majorly turned up air to protein skimmer+ shortd and redirected both spray bars (one from wet/dry filter and one from canister filter) towards surface enough to break surface tension = major increase in usable oxygen for fish = exhausted fish

Problem 2) to few rocks/caves/resting places for fish (in fact only one 4 pieces of decor and they are small, only one is big enough to hid or sleep in = exhausted fish
Problem 2a) Need stronger biological nitrate control = slightly elevated nitrate levels.

Solution to 2 & 2a)Will be adding Live rock to provide shelter/caves as well as to assist with nitrate control.

Problem 3) Adding to many fish at one time = overloading the tanks eco support system.

Solution to 3) Add only one or two small fish at a time and waiting untill the tanks eco system has caught up nefore adding any more.

Also to slowly strengthen and improve over all quality of water I will be doing 25% water changes only replacing with "Real Ocean water" from Catalina Water. Except when replacing due to evaporation.


Thank you to everyone for your insights, thoughts and advice..it seems all the little things have added up to create one bigger problem.

The kinda rule of thumb with Live Rock is 1 Kilo per gallon of water, I have less than the kilo per gallon and my fish seem fine, you do need the Live Rock as this is your main Filteration in the tank or it should be.

TBH if I were you I would re-home the Trigger for a while and try another fish in, then bring the trigger back to see if that works, you can set up a small quarntine tank, just use water from your tank to fill it, get some hiding places plastic pipes are fine, add a heater and you don't need any sand or anything like that since it will be temporary.

to me looking at your situation I would say the Trigger is the problem, as I said earlier the air bubbles many argue against it some say it makes no difference.

The trigger may look peaceful enough but you can't keep an eye on your tank 24/7 do you have anything else in teh tank like Starfish by any chance.