Hello all, this is my first post here so I'm sorry if I am over/under- informing. Here's my dilemma;
My corydoras are dying after adding them to my main tank after being perfectly healthy in quarantine.
Just over a month ago i got 6 trilineatus cories (juveniles about an inch long). And inherited a nerite snail. I put them in a 10 gallon quarantine tank. I proactively treated with paracleanse after a week. The next week i noticed one had a small red spot and another had shortened barbells (i believe they were short from day 1) so I treated with maracyn. After treatments and a total of 4 weeks since day 1, i added them to my main tank. At this point in the QT tank they had been perfectly happy, super active, and had great appetites.
After 1 day in the main tank (yesterday) one died seemingly out of nowhere. Today another died. None seem very active but show no sign of disease, injury or stress. They did not seem excessively stressed from the move and were actually out and exploring as soon as I added them. They were actively looking through algae looking for food. My main tank is planted, with eco complete.has been set up set up for about 4 months. I cycled with ammonia at first, then after finding bladder snails i only added food for them, and left any decaying plant matter as a source for ammonia. The cycle has remained strong and stable with about 30 small bladder snails as the only inhabitants prior to the cories. Different algae growing. Water parameters have not changed as of the move (checked 3 times since they died with strips and API master kit) changed 30% water today as i do weekly. Any idea what is causing these sudden deaths to previously healthy active fish? They were fed frozen bloodworms and emerald entree for the first time 2 days before being moved (brand new purchase, they ate it happily) Snails seem to be doing fine. Could the frozen food, or algae have caused this?
Both tanks get water from the same tap source.
- 55 gallons
-Filter: Tidal 110 (rated for 110 gallons)
-Ammonia: 0 (my water has 2ppm ammonia from the tap. I treat all new water with prime, and it drops to 0ppm by the next day)
-ph: about 7.4-7.6
-temperature :78 degrees Fahrenheit
-hardness: about 3dkh and 3dgh
-substrate eco complete.
-driftwood, and live plants present.
- weekly 30% water change treated with Prime.
- weekly add Easy green fertilizer, and easy green liquid carbon every other day (algae inhibitor)
- purigen in the filter to help with tannins from driftwood (mopani)
- no contact with harmful chemicals or anything else added.
Any help would be appreciated.