Continuing life in the Biorb

Update : After some rather odd spam complaining about the overcrowding of my tank (of 9 tetras) and how I should upgrade to a 10 gallon tank, I should say the tank is 16 gallons, and as I already said – I knew the limitations of the tank before I bought it and was never planning to put that many fish in it. So get off your high horse!

Life continues in the Bioorb! After some unsettling events, which i will get to in a minute, the Bioorb 60 Life is settled into a happy lifestyle. The stock is at the moment, the 3 original black neons, 3 penguin tetras, 3 zebra danio and 3 amano shrimp. I realise that the recommended stocking for these species is 6 or more in each group, and I was planning to up the levels in each species but we will have to wait and see.

So far they seem to be working well together, the zebras and are boisterous and chase each other and the penguins around. At first I was worried about one of the penguins being aggressive but the zebras seem to have since balanced out. I don’t know if it is because it is a relatively small tank but the groups of three seem to work very well, the neons aren’t nervous and none of the fish seem to be skittish at all.

Now to the unsettling events. I added three guppies to the tank, trying to add a little colour to the tank. At first, for a day or so they all seemed fine, then one died unexpectedly, with no symptoms. So I took it out and kept a close eye of all the fish. A couple of days after on of the 2 remaining guppies developed symptoms of bloat. That is swollen body, sticking up scales and general lethargy, even though he was swimming ok. So I took him out and put him in a quarantine tank.

I know moving him was not the best for him because of the trauma of a move. But I tried to match the water conditions but adding some from the old tank, I added medication for bloat but from what I read on the web there isn’t much hope once symptoms appear. The upshot is he died. And then in another couple of days the other guppy displayed similar symptoms and died as well.

Throughout this episode I checked the water levels, temperature, food and is the fish were being attacked. Everything was fine and only the guppies got sick. I medicated the rest of the tank with a natural aloe vera and tea tree combination and all the remaining fish (and shrimps are fine).

So any ideas what happened? Were they sick when they arrived? Was it the stress of moving tanks? Im fairly sure the water is fine, the shrimp are particularly sensitive so I would expect them to have been affected. The water here is particularly hard but the pH was fine. Any suggestions, anyone?