I really would appreciate any input/advise in regards to a major problem i have with my fish dying at the rate of 1 per day.
I have a 525 litre tank (DD 1500S), that has been running since early April. Aquarium consists of a 2 inch living sand substrate and 60 Kgs of live rock and the cycle lasted probably under 1 month before all water parameters were good.
Since I stocked with a variety of small fish, about 5 each week, consisting of 5 x Blue Reef Chromis, 5 x Grren Chroomis, 5 x Sunshine Chromis, 4 x Azure Damsels, 2 x Banggai Cardinals, 1 x Blue Cheek Goby, 1 x Royal Gramma, 1 x Male Flasher wrasse and 1 x Female Flasher Wrasse.
CUC consists of 10 x Turbo Snails, 6 x Red Legged Hermit Crabs, 2 x Emerald Crabs and 1 x Brittle Starfish.
All water parimeters have remained consistently good, with no spikes and I perform 10% water changes fortnightly. Fish and inverts had been thriving and appeared really happy with good appetites and no agression.
I recently went on a weeks holiday leaving on Wednesday night and asked the inlaws to feed the fish with frozen food (Mysis and Brine Shrimp) on specific days of the week until our return home early hours of Friday the following week. The days to feed were supposed to be Sunday, Tuesday and thursday, as we gave a large feed the night before we left and also had an auto feeder setup to feed pellet and flake.
We set up a camera to view tank while away and noticed the fish were fed the day after we left (Thursday) when it should have been sunday and also noticed that the auto feeder was not removed before the jump guard was lifted and it moved from horizontal to almost vertical, forcing the food inside to move right to the back of the feeder. This I believe meant that when the feeder spun on its schedule the pellet and flake was not picked up by the feed bucket (for want of a better word) so no or little food was actually added.
The next time the fish had frozen then was Sunday so, 3 days with little or no food and I guess some competion for what was given potentially could have led to agression and maybe some fish were stressed, although I'm not certain. This may then have triggered an illness as when I got home there were 7 fish missing/gone with no sign of badies.
First thing I did was to test Amonia, Nitrite, Nitrate, PH and Alkalinity and all paremeters were still good. Then I looked at all the fish and noticed no sign of Ich but a few had slightly damaged fins and a bit off colour. My next thought was possibly Velvet, but as I'm pretty new to tyhe hobby I have not seen this up close.
That day i performed another 10% water change and usual tank maintenance and thought all was ok, but the next day I lost another fish and so the trend has carried on, each day another 1 or 2 go.
I treated with Polyp lab medic assuming it could be a parasite but after a few days fish were still dying so I then used an antibacterial water coonditioner and stopped the treatment with Medixc as I thought it may be a bacteria issue and not a parasite one. Again I'm still losing fish but now desperate to know what to try next or how to treat.
My next steps have been to buy a QT and I'm planning to add the remaining fish to it and treat with copper?
Anyone have better ideas or any idea what it could be? - Please help!!