Barbs keep dying

[Scoop47501]

Hi. I have a 26 gallon bow front tank and I'm having trouble keeping my barbs alive. Tank is cycled and temps are around 74 degrees. Other spics are
Nitrate = 20 or below
Nitrite = 0
Hardness = 75
Alkalinity = KH 180
PH = 8
The tank has two tigers 2", two Albino Tigers 1", two Green Barbs 1", and two Rosy Barbs 2". Also one Pleco 5"
I only add fish when I lose one because I'm affraid I'll lose my bacteria.
My fish seem fine for a couple weeks then one or two will start to hide then lose it's ability to swim well, then dies later.
I feed them flake food by Nutrafin Max and some brine shrimp once a week.
I do weekly 25% water changes using drinking water from Wall Mart trying to get the PH down.
Thanks in advance
Scoop

 

[Holly9937]

What exactly do you mean by lose its ability to swim well? Is it sinking, swimming upside down?

 

[shadrac]

I would rais the tempature a few degrees and insted of feeding the the brine shrimp i would switch to frozen blood worms that mite help and if that dosent i would take at least two fish out and montiter it to see what its dose

 

[kjd277]

I agree, raise the temp a little and also lower your ph. I believe they like it around 7(neutral).

 

[Analog Saint]

the pH shouldn't matter at all, if they were acclimated correctly. If the LFS is in the same area, then it is likely that the barbs were kept in the same type of water (unless they R/O all their tanks). In most every case, a constant pH is much more important than a given number. Breeding is about the only time where pH comes into play, as it can affect sex ratios, and more importantly, whether or not the fish breed at all. Plus, if pH shock or temperatures were the culprit, most likely, the barbs wouldn't make it two weeks. I would agree that 74 is a bit low, but probably not enough to kill tiger barbs.

Any symptoms present besides odd swimming and eating? Do the scales stick out? Is there any bloating? Are there any lesions? Do they just stop swimming altogether and just lay against the substrate? I know tiger barbs are rough company, but is there bullying going on, above and beyond normal tiger barb activity?

 

[Scoop47501]

I will raise temp a bit. The only reason it was where it was is I read some place that some of the Barbs (Rosy) like it cooler and I was trying to make it right for all.
There is no bloating, Ick, scales sticking out ect.
As for the swimming weird I was referring to slow , and sluggish, going to the top for air then sitting at the bottom alot. Just swimming goofy sometimes .
I do have an air stone going so I don't think it's oxygen.
Could it be that the bottled water has chorine it it. I don't know if it does but have not been treating it. The only reason I use the bottled water is my tap water is way soft and highly akaline.
Thanks for the tips so far
Scoop