Borelli fry dying

[Aarontg98]

Hi guys, I've had a batch of (at the start) about 25 Borelli fry (20 now). They are from 2 batches (1 & 1.5 mths) that I received from a friend a fortnight ago. They are housed in a 10-gallon tank that has some hornwort, a strong sponge filter with ADA Amazonia soil as a substrate. About weekly, I noticed that I was getting losses of between 1-2 fry a week. They would sit on the bottom and slowly become more lethargic over the following days, refusing to eat, tilting to one side and gliding over the substrate with a tail-heavy shimmy. When they died days later, they were relatively skinny. The other fry don't show any symptoms and look robust and healthy. I do weekly 50% water changes and feed them twice a day: once with live BBS and another with Dr Bassleer's M Pellets. My water parameters show no Nitrites nor Nitrates. PH is around 6.5 and temp fluctuates between 25/26C to 28C. I use aquarium salt 1 tblspn per 10 gal and I squirt my BBS straight into the tank. My water changes don't contain salt, however, to account for the change in salinity. I notice that the fry dying are almost always the younger fry from the 1-month batch. The largest fish (2.3cm) in the tank is more than 2 times the size of the smallest (>1cm). However, I'm not seeing much aggression (the tank sits on my work desk) aside from the usual flaring and chasing. The only other tankmate is an unidentified snail that came in the hornwort that I tolerate on the grounds that it helps to clean up the detritus. Does anyone have any advice/experience with this?

 

[MacZ]

I see three things that might add up too quite a lot of stress on the little ones: The substrate is not apistofriendly, aquarium salt is in my experience generally a bad idea for softwater fish (even though borellii don't necessarily live in the softest water there is, tannin sources are the better choice for the same effect) and the temp-swings also don't sound too good.

Have you compared your friend's parameters with your own? Has said friend used meds a lot on the fry or the parents before he gave them to you? Can you post a picture of the whole tank?

 

[Samala]

How old is the ADA Amazonia? This is known to leach ammonia into the aquarium for a considerable period of time; even more so without significant plant growth. That would be my first suspect. Do the fry have reddened gills?

The size variation in fry might mean the smallest ones are simply being outcompeted for food. Smaller fry also are the least likely to take non-live foods in my experience with borellii so far. Can you up the amount of BBS? Provide it more frequently? The little ones under 1" love microworms and larger fry seem to ignore it in my tanks. Can you get some?

I would definitely stop the addition of aquarium salt and dramatically increase the amount of water changes. I change at least 50% every day on borellii growout tanks. It really does make a difference in fry growth rates. While I've used salt to treat white spot/ick in borellii it was only for a few days. Would not recommend doing this continuously unless definite reason to do so.

On temp swings: This swing itself isn't too terrible and wouldn't worry me so much although 28C seems a bit high and I'd worry about dissolved oxygen. That's the about the highest I'd ever let my tanks get without intervening. (My tanks are ambient and regularly fluctuate 2-3C throughout a day/night cycle this time of year.)

 

[MacZ]

How old is the ADA Amazonia? This is known to leach ammonia into the aquarium for a considerable period of time; even more so without significant plant growth. That would be my first suspect. Do the fry have reddened gills?

At a pH of 6.5 Ammonia is not acutely toxic. Was thinking of that too, but in the acidic environment not a problem.

Otherwise full agreement.

 

[dw1305]

Hi all,

I use aquarium salt 1 tblspn per 10 gal ........

Why?

cheers Darrel

 

[Aarontg98]

I see three things that might add up too quite a lot of stress on the little ones: The substrate is not apistofriendly, aquarium salt is in my experience generally a bad idea for softwater fish (even though borellii don't necessarily live in the softest water there is, tannin sources are the better choice for the same effect) and the temp-swings also don't sound too good.

Have you compared your friend's parameters with your own? Has said friend used meds a lot on the fry or the parents before he gave them to you? Can you post a picture of the whole tank?

Hi,

Thanks for replying. Parameters are relatively similar, no meds used. Yeah, I've been trying to get the aquarium salt out of the tank with water changes. Temp changes are down to ac in my room. It gets that hot because of ambient temperatures.