Odd swimming behaviour/deaths in new tank

[Roland6543]

Hi all,

So I just set up a 70g freshwater tank. After a day settling in (I added the appropriate quantity of dechlorinator, plus some salt for freshwater tanks), I decided it time to buy some hardy fish to begin the cycling process. I put in 3 Zebra Danios (they came with a second, smaller tank I bought), plus 4 new small Danios and 4 Tiger Barbs that I bought from a big box store.

On the way home from the store, one of the new Danios was swimming in a crazy corkscrew pattern. By the time we got home he was swimming normally again. Stress I thought. We acclimatized the fish to the new temp by floating the bag, then added some water from my tank to their bags in two stages, then finally netted them out and popped them in the tank.

Within 6 hours 1 Danio was dead, and another was also doing the corkscrew olympics, and shortly also dead. I took them out. By the next morning of the 2 remaining newly purchased Danios, one was missing (half of him showed up later in a Barbs mouth), and another spiralling out of control (which I euthanized in the freezer).

I figured a bad batch of Danios from the store, since the 4 Barbs and the older Danios were doing fine. To get back to the original planned stock level I went to a different specialized LFS and bought 3 more small Danios. By the next day one of the new Danios from the small LFS is showing the same symptoms.

My tank is obviously still in the early stages of cycling. Results are:
Day1 Day2 Day3
pH 7.4 8.0 8.0
NH3 0.10 0.10 0.10
NO2 0.00 0.25 0.00
NO3 0.00 0.00 0.00

I'm thinking one of the following could be happening:
- The chemistry in my tank is causing this (Unlikely because the first symptom was on the way back from the pet store).
- Both stores that I bought the Danios from bought them from the same supplier and they are carrying the same "issue".
- The 4 small Danios that I bought from the big box store brought in a disease that is beginning to spread to the other Danios (the 3 older Danios are still doing OK).

What do you think? Any suggestions on how to deal with this?

 

[Thyra]

Welcome to the forum! I really don't think I can help you, but I am sure someone else will have some ideas. The one thing I noticed was the big change in pH - did you do something to cause that? That big of fluctuation would be very harmful to your fish. Also IMO salt is not really good or necessary in a FW tank. You could quickly wind up with salinity problems. Here is a website with more info:

Aquaworld Aquarium - Adding Salt to a Freshwater Aquarium
Good Luck!

 

[Thyra]

Welcome to the forum! I really don't think I can help you, but I am sure someone else will have some ideas. The one thing I noticed was the big change in pH - did you do something to cause that? That big of fluctuation would be very harmful to your fish. Also IMO salt is not really good or necessary in a FW tank. You could quickly wind up with salinity problems. Here is a website with more info:

Aquaworld Aquarium - Adding Salt to a Freshwater Aquarium
Good Luck!

 

[Roland6543]

I didn't add, or knowingly do anything to change the pH. Question is: Should I do something to bring it down?

Regarding the salt. I think through regular water changes, I'll let it slowly work its way down.

 

[OrangeCones]

Hello Roland6543, welcome!

That does seem to be a huge swing in pH for a 24 hour period, which would certainly adversely affect fish. It doesn't explain the odd behavior in the bag before being released though.

I wouldn't suggest doing anything to raise or lower pH, but if you did not do anything to change it, I would suspect faulty readings. What type of test kit are you using (strips or liquid) and do you knw the expiration date?

In the long run, you may run into issues with the tiger barbs. They are noted fin nippers unless kept in larger shoals, where it is more likely they will pester each other and leave others alone.

 

[Sinking Bubbles]

Hi Roland6543

I’ll have the experts judge the PH and accompanying factors

Informative

I have narrowed down my suppliers to two. Interesting though is their difference in their approach to salt.

1. The owner of the Koi Farm firmly believes in salt (100 grams per 100 liters) – Yes, that is high but for Koi with a higher tolerance it is most probably fine

He also breeds various other species of tropical fish and also adds a certain percentage of salt

2. The owner of the local Aquarium Center believes in salt only for temporary medicinal purposes

The Koi Farm fish I can add almost directly to my freshwater tank (which contains a small amount of salt) and have had minimal loss on any fish acquired from them

Purchasing from the ‘non salted’ Aquarium Center I have to acclimatize the fish, slowly weaning them to the same salinity as the main tank otherwise there are some loss, depending on the fish type

Figure out what your characteristics of your local water are and adapt to that

Enquire at the store / breeder etc to what their approach re the use of salt etc is.

Stick to 1 or 2 places where you purchase your fish and you should have much less loss

Enjoy!

 

[Roland6543]

I think I'll do drip acclimation in future. That should compensate for any significant water differences.

Thanks for the great advice.

 

[Roland6543]

Forgot to mention.... I'm using the liquid API test kit, and its expiration date is 2017.

 

[metsrangersfan15]

exactly how much salt did you add, and of what kind?

 

[Roland6543]

I added 180 mL for the 70gallon tank of Mars Fishcare Aquarium Salt for Freshwater Fish, which is a little less than the recommended dosage. I've since done a 20% water change not using salt, so its obviously diluted that concentration down by 20%.

 

[metsrangersfan15]

that would be the correct amount, so that shouldnt be the problem. you just have a gravel substrate?

 

[Sinking Bubbles]

Hi metsrangersfan15

I use coarse sea salt purchased from the Koi Farm (Non iodated and slightly damp).

Compared to the Koi Farm owner I use much less salt. He uses 1000 grams per 1000 liters which would be 204 grams on my 204 liters.

Just looking at the mere volume of 200 grams of salt I decided to rather stick to the average salt advised on various forums of 4 grams per 4 liters. (many times quoted as 1 teaspoon per gallon)

Therefore I prefer 50 grams per 200 liters (1/4 of his ratio) and then keep to this ratio when doing water changes.

A lot of the forums give measurements in teaspoon, tablespoon and dessert spoon quantities.

Just like the coffee made by two people with exactly the same ‘spoon’ tastes different the measuring of salt or any other substance with a spoon will differ from person to person.

Please stick to weight rather than to volume unless otherwise stated.

Ave weight of Coarse Salt per 5 milliliters is 4.01 grams taking into consideration that salt does absorb moisture from its surroundings.

Below a nice link for volume to weight conversions :

Volume to Weight conversions for common substances and materials (mobile)

Keep in mind that salt does not evaporate.

Depending on climate / humidity etc you can have a high or a low water evaporation rate.

Once a week I would advise during a 10-25% water change to not add salt to compensate for any salt build up.

 

[Roland6543]

Yes, just gravel substrate, although once cycled I want to add a few clown loaches (my favourite fish), so according to what I've read, I may need to add some sand.