Glofish keep dying...

[Fishmom84]

Hello all, I have a relatively new 10g tank that I’ve had running for a couple of weeks and just added a danio and barb to the other day. I put in the fluval cycle when setting it up and followed the instructions for a new tank and for when adding fish. The barb died the very next day and the store tested the water and all of the levels were fine and the ph was 7.5-8 when I tested at home. So I got a few more danios and 2 barbs and after a few days, one died. I had noticed the barb was swimming downwards at an angle and now the danio i started off with and one of the new barbs are swimming at the surface.

I thought maybe they weren’t getting enough dissolved O2 in the water so I removed some of the water so the water from the filter would “waterfall” into the tank agitated the surface more. Otherwise, I’m at a loss of what to do. I’m definitely not getting anymore until I solve this problem. Any constructive advice is appreciated!

 

[Aiken Drum]

I strongly suspect your tank isnt cycled. Do you know what your water patameters are? You have only stated the pH.

Ammonia
Nitrite
Nitrate
pH

Just saying that the store tested it and says its fine isnt sufficient. Did they give you the results? If not, get a test kit (preferably liquid test) and do the test yourself. Depending on the store and employee they may not know what they are talking about. My local fish store, i would trust because all the emoyees are hobbyists. The big box store i wouldnt trust.

Unfortunately, bottled bacteria like Fluval Cycle isnt likely to do as advertised and won't instantly cycle a tank. At best, they will cut the time to cycle a tank from a few months to a few weeks.

If you arent able to confirm water parameters, first thing to do is a water change. 25%. Then do your best to get those water parameters.

 

[Fishmom84]

Yes, they told me there was no ammonia and no nitrates and nitrites. I found the rest of the fish dead this morning leaving just one very active looking danio left. I’m so upset that they would tell me I should be ok to get fish and that they probably died of “shock.” How long should I let the tank run before trying again? I had ordered strips but I’ll get one of the liquid kits. I had original got these for my daughter so she’s pretty heartbroken that this happened and I’m left feeling like the grim reaper for fish... I hope at least the little purple danio continues to do fine. Thank you for your help.

 

[Fishlegend]

Barbs need a bigger tank then a ten g they are schooling fish 2 is not enough. Glofish are genitive modified. Some may have very bad deformation

 

[Aiken Drum]

Sorry about your fish. If there is no nitrates then the tank wasnt cycled. Nitrates in the tank show that your ammonia is being consumed by the beneficial bacteria and turned to nitrites and those nitrites are being consumed by different bacteria and turned to nitrates. Nitrates are much less harmful than ammonia and nitrites and are removed from the tank with waterchanges.

With regards to starting up again, you have to decide whether to do a cycle with fish in the tank (fish in cycle) or without fish (Fishless cycle). How much do know about the nitrogen cycle? It is essentially the process of growing sufficient beneficial bacteria to convert ammonia to nitrite and then to less harmful nitrate.

Fish in cycle is where you start with a few small, hardy fish (1 small fish per 10g is typical). Check water parameters daily, and do 25% waterchange whenever you see ammonia or nitrite. When you start to see nitrates and after 24 hours you arent seeing any ammonia or nitrite you can increase the number of fish. This gets some fish in the tank quickly, but you are putting fish in less than ideal water conditions and can take a long time to be fully stocked. This is the most common method of cycling and what most newcomers resort to because they have put fish in without knowing about cycling.

Fishless cycle, you replicate the natural process of having fish in the tank by adding pure ammonia, or fishfood and letting it decompose. This typically takes 4 or 5 weeks. You are making sure the aquarium is cycled before putting fish in and after the 4 or 5 week period you can pretty much stock the tank fully. This can be a bit fiddly, having to measure out ammonia etc and doesnt always go as planned.

Have a think about you want to move forward and let us know. Do some research on both methods. There are pros and cons with both. With either method having some established filter media or bacteria in a bottle (eg seachem stability) will speed up the process.

Edit. Just reread your post and you still have 1 fish in there. So going forward, unless you want to rehome your danio then i would go with a fish in cycle.

 

[KaylNeko]

If there are no nitrates, then you're not cycled. Only time I've seen zero nitrates on a cycle tank was when it's heavily planted and relatively lightly stocked. Go with what Aiken said about a fish-in cycle. Unfortunately, glo-fish aren't the hardiest fish around, so you kinda need to baby them a bit.