Shy, Thin Subadult Bloodfin Tetras

[mimi86]

I'm looking for some help from tetra experts on what I might be doing wrong, if anything. My Green Fire Tetras are extremely shy and not eating as enthusiastically as they used to.

In early March I received a shipment from an aquabid sale for what were supposed to be 6 kubotai rasboras. Instead they sent me 9 Green Fire Tetras, aka 'Rathbun's Bloodfin Tetras' aka Red-flanked Bloodfin Tetras. They get to be 2" long and these were a little smaller than neon tetras at the time so they were juveniles, I consulted some folks from a well-regarded fb group who even said they were so young they couldnt accurately identify at first.

These guys ate *ok* while in quarantine, they were in a 5gallon sterilite tub for well over a month because I had to get a bigger aquarium (since these were not the kubotai rasboras I ordered). I fed them mostly flake foods as they ignored my ground-up pellets. They got Extreme Krill Flake & Spirulina Flake, baby brine shrimp, and egg yolk most of the time. They went through QT with levamisole, maracyn 2, and sulfaplex for 1 week each (but they were in QT for longer overall). No signs of illness.

I ended up putting them in a lowboy/riparium style setup in early/mid April. I took a 40 gallon and cut it in half. Specs:

Size: 20 Gal (more like 17g because of hardscape and since I don't fill it all the way)
Filtration: 2x sponge filters rated for 15 gallons, with directed return flow above the water to create surface agitation. I've also included an airstone for more aeration
Substrate: White sand with lava rock in the back for BB growth (and hydroton clay pellets for the riparium plants)
Hardscape: Cypress driftwood, seiryu stone
Tankmates: 6 pygmy corydoras, a handful of malaysian trumpet snails
Lighting: 2x Hygger Planted 24/7 suspended 12" above the water surface, on a 24 hr daylight simulation cycle.
Moderately planted with salvinia floaters for cover (i say moderately because all the underwater creeping jenny I had melted as soon as it started to emerse so I'll be adding more). Riparium plants were mostly purchased bare root or otherwise washed REALLY WELL and transitioned to emersed growing in a separate jar to mitigate fouling of the tank water. I have antherium, maidenhair fern, english ivy, stonecrop sedum, creeping jenny, philodendron, purple waffle, polkadot plant, and sweet potato vine)
I test this tank more frequently than my others, thinking I was having a chemistry issue, but it seems consistent:
ph 7.2
ammonia 0
nitrite 0
nitrate 10
temp: 78
KH: 5 (API test #drops)
GH: 15 (API test #drops)

These guys do nothing but hide behind/inside/UNDER the hardscape. They sometimes come out if they see food drifting down but often end up ignoring it. They're not really growing much and not 'filling out,' I feel like even if they're longer theyre proportionally thinner than when I moved them from quarantine to the new tank. The only food they really LOVE and consistently eat is the baby brine shrimp. I was toying with the idea of removing the floaters and moving the filters all to one side to create flow, but if they're timid then maybe they'll feel more exposed. Do these guys eat better at certain times of day? Is this just how tetras are in general, and I have picky eaters on top of it?

(in the pic the white spot on the far right tetra's flank is a falling crumb of egg yolk, it was one of 3 pics i took in rapid succession and it's not in the 2 other pictures)

Edited May 23, 2021 by mimi86

[ARMYVET]

I am sorry I cannot help you solve your dilema but had to tell you ...that tank looks incredible. WOuld love to see some better close up pics of it!

Hope you figure those guys out!

[Streetwise]

I love bloodfin tetras, and they are among my most extroverted fish. Perhaps you just need more of them.

[Hobbit]

You have a beautiful setup! I’m not a tetra expert, but from my (limited) experience raising fry, if I were in your shoes I’d go ahead and feed them lots of baby brine shrimp until they fill out again. Maybe eliminating one stress (food/hunger) will help them deal with the other stress (being shy). You can always transition them to easier foods later. One thought is that perhaps they lost most of their gut bacteria during their quarantine treatments and are now pickier because they have more sensitive tummies. But it’s been a few weeks so I wouldn’t expect that to be an issue... also I’ve never heard of that happening in fish. 😄

I agree that getting more fish may help them. Perhaps even a different kind of fish, like platys or guppies or something that’s very active. Seeing other active fish will signal to them that it’s safe to come out.

One last thought—I can’t tell from the picture, but are the sides of the tank clear, or covered? If they’re clear, you may try covering the sides with a piece of paper so they only have one open side to “worry” about.

[mimi86]

On 5/23/2021 at 9:50 AM, ARMYVET said:

I am sorry I cannot help you solve your dilema but had to tell you ...that tank looks incredible. WOuld love to see some better close up pics of it!

Hope you figure those guys out!

I'm probably going to re-do it (different substrate, plants) , maybe I'll post a build journal here!

On 5/23/2021 at 5:37 PM, Streetwise said:

I love bloodfin tetras, and they are among my most extroverted fish. Perhaps you just need more of them.

How big of a school? I have 9 of them

On 5/24/2021 at 12:19 AM, Hobbit said:

You have a beautiful setup! I’m not a tetra expert, but from my (limited) experience raising fry, if I were in your shoes I’d go ahead and feed them lots of baby brine shrimp until they fill out again. Maybe eliminating one stress (food/hunger) will help them deal with the other stress (being shy). You can always transition them to easier foods later. One thought is that perhaps they lost most of their gut bacteria during their quarantine treatments and are now pickier because they have more sensitive tummies. But it’s been a few weeks so I wouldn’t expect that to be an issue... also I’ve never heard of that happening in fish. 😄

I agree that getting more fish may help them. Perhaps even a different kind of fish, like platys or guppies or something that’s very active. Seeing other active fish will signal to them that it’s safe to come out.

One last thought—I can’t tell from the picture, but are the sides of the tank clear, or covered? If they’re clear, you may try covering the sides with a piece of paper so they only have one open side to “worry” about.

I've definitely been hatching more baby brine lately to see if it helps. I do have guppies in other tanks, I was hesitant to add them not knowing if the tetras were sick or not, but I'll try it! I'll also see if I can get some garlic based food for their tums--I didnt consider that all the antibiotics might do that! The sides are not blocked immediately but theres a curtain on the left hand side and a wire rack on the right hand side where i have some tools and food, so they can't see out into the room on the sides'

 

Thank you!

[Colu]

It could a shadow on the tank causeing them to hid as you approach the tank