Spawning Report: Nothobranchius guentheri

Submitted by: Dave McGrew

Started: 08-26-2022

Completed: 10-11-2022

Species: Nothobranchius guentheri (Redtail Notho)

I owe my introduction to Killifish entirely to PVAS Club member Bob Bock, who in my book will always be indexed under "Master Aquarist." He got me into breeding Fundulopanchax scheeli, and introduced helpful info on other species via YouTube videos like this one.

Bob invited me to connect with MAKO (Mid Atlantic Killifish Organization) for some zoom meetings through the pandemic. This introduced me to other Killi enthusiasts. I began talking with them, and learned a good deal about African annuals from Clay Crawford, out of NJ. I connected with Clay in Lancaster, PA and traded him some F. scheeli for some N. guentheri.

First, let me share some preparations...

I set up a 10 gallon aquarium. I decided to make it a planted tank. I realize this is out of norm for most breeders -- plants can be a bother, distraction, etc. But I like fauna. And I do not think it negatively impacted the breeding process anyway. In this photo, you can see the plastic spawning dish set up without peat moss / coconut fiber. The stone holds the dish down.

The process of getting everything ready included: buying plastic breeding dishes, exacto-knife, cutting hole opening, peat moss, hot pot, boiling peat moss (or coconut fiber), etc...

What annual killis like Nothobranchius guentheri need is a "soil" location to spawn in daily.

So, eventually I got a nice trio via Clay. The male really colored up nicely after a few weeks...

I started feeding a diet that included live baby brine shrimp, frozen foods -- brine shrimp, and blood worms -- and let them mature. Eventually it became obvious that they were spawning every single day.

Now, this was back in the late winter of 2022. I'll skip ahead over a few bumps in the road . . . which include . . . rupturing my achilles tendon, cracking this tank with the fall of a crutch I was using during recovery, subsequent loss of one female from the transition to another tank . . . a failed attempt to hatch out eggs from this batch (which was spawned in coconut fiber) . . . a new reset using peat moss . . .

Which brings me preparation for the past few weeks. One thing that is important is to pull the peat moss / spawning soil, dry it out, and check for eggs. Then part way through the "dry season" it is important to check eggs again to ensure that some are "eyeing up" -- which refers to the actual eyes of fry visible in the eggs. Here are a few photos and videos of all that process:

I remove the spawning container, empty the water, pour the soil out into a fine mesh net, them dump out and spread out on several layers on paper towel to dry over night.

I store them at room temperature in freezer bags up on a top shelf of my fishroom.

Zoomed in, you can see the eyed-up eggs from the peat moss.

Hard to see, but this is what a search for eggs in the peat looks like...

For N. guentheri, the dry season is only a two-month wait. For others (e.g. N. rachovii) the what can be as long as 6-months or more.

It is important to maintain a good colony of vinegar eels. I use a narrow-neck bottle, fill up most of the way with vinegar eel culture + vinegar with the mother, put filter floss down the "throat," and then use clean tank water to fill up the top. The water stays up, and eels swim through the vinegar up into the water making harvesting (1) easy, and (2) less likely to crash your tank with acid.

Now comes hatch day. This was 08-20-2022 for me.

I use a 2.5 gal. aquarium. I have a mini filter bag set in the tank with some ammo chips in. My goal is to stabilize the water. I also use a mini sponge filter with the uplift _above_ the water surface to keep from over disturbing the water. I do also use a Ziss airstone on a rigid airline with a very minimal, fine bubble flow.

I add ca. 3-4 inches of tank water from my discus tank. Then I dump in some peat + eggs. For this batch, I only hatched out 1/2 of the eggs.

After about 24 hrs, the fun begins!

Now, by Monday, I tried something new. I'd been feeding vinegar eels so far. But I wanted to see if I could use green water as a transition for them until the fry were large enough to eat baby brine shrimp. Since it is summer, and I have some water gardens going, I went for it. Very successful -- but not without some cautions.

(my two-year-old making noises in the background . . . standard fare for the fishroom)

I've also begun adding a skiff of java fern with each feeding. My thinking is just that there is a balance for producing and maintaining infusoria, and the addition of these greens may be beneficial here.

By August 26, 2022 the Killis fry definitely transitioned over to live baby brine shrimp. Their belies are orange from feasting on BBS.

As of 08-30-2022, the green water is still too cloudy to accurately account for all the N. guentheri fry. Fresh, cycled water was added to help dilute some of the build up effects from heavy feeding. Waterline was brought above the uplift of the sponge filter, to move water around a bit more.

On 08-31-2022, the 2nd half of the bag of peat-moss + eggs was added to a flow-through floating tray in a cycled 20 gal long. This will be a back-up / alternate hatching setup.

It is basically composed of a Tupperware container with a styrofoam collar, slats cut through the sides with coarse canister filter foam cut to fit through to allow water flow through while protecting from fry exit.

By 09-05-2022, Labor Day in US, the first 1/2 of the bag has matured sufficiently to raise water and add more Java moss. Water changes are being performed more now - ca. 30% each week or so. I use cycled water from a recently water-changed tank — not straight tap water.

Same date, the 2nd 1/2 of N. guentheri fry have hatched, seem to be really thriving in the floating flow-through set up. I’ve added a very light air stone to break up bio film on surface and keep O2 levels balanced. Most fry are now happily on to eating BBS. Some Java moss added as well to keep the biome balanced. My “helper” is at hand…

-- Long Intermission here, during which: (1) the first batch in the 2.5 gal aquarium all suddenly died, likely from water quality crash after being overfed -- a sober reminder that small aquariums are very difficult to balance water quality with. (2) the second batch, hatched out in the floating flow-through fry tray thrived, and as journaled below, were released into the full 20 gal. long aquarium -- a reminder that Dean's fry system is really a fantastic way to hatch out and raise up fry.

Here is a look at the N. guentheri fry in the tray, taken on 09-26-2022

And it's release day! Here they go, out into greener pastures...

Here's a video, showing the fry enjoying their larger digs. Taken on 10-01-2022

By 10-09-2022, the N. guentheri fry are just beginning to show off some color. They have passed the 1-month critical threshold, and are ready for BAP submission...

In conclusions, here are my notes on the species from top to bottom...

SPECIES

Nothobranchius guentheri

REPRODUCTION

Annual Killifish

Soil / Substrate Spawner

8-week egg drying period required

AQUARUM CONDITIONS

Dried eggs with peat or coconut fibers are dumped into a small aquarium or tray with aquarium water. In this case, a shallow floating flow-through tray designed on the concept from Dean Tweeddale was used for hatching. The water chmistry was shared with the larger 20 gal. long tank that the tray was floated in.

At time of BAP submission, the following measurements were made using API titration test kit

KH — 2-3 drops

pH — ca. 8.0

Temperature — ca. 80-82 F

Ammonia — 0 ppm

Nitrite — 0 ppm

Nitrate — ca. 40+ ppm (API titration test is old...)

Water Source — public / city water

Water Changes — With killis, I do not complete large water changes. There is more topping off than actual changes. A typical 20% change is performed every ca. two weeks, otherwise the tank is topped off. I will note that I like to keep the salt from baby brine shrimp in the tank. Salt doe snot evaporate, and Killis do well with some salt slowly building up in their water.

Filtration System — two sponge filters

DECOR & ENVIRONMENT

Live Plants — light Java moss, some Java ferns, several small marimo moss balls

Caves or Similar Hiding Places — Sponge filters provide some cover; floating fry trays also provide some muting of lights

Substrate: Black Diamond Blasting Sand; light touch of crushed coral

Lighting Type and Timing: 5,000-K shop light LED filtered through cabinet liner grid for diffusion

FEEDING

At first hatching, vinegar eels and New Life SPectrum GROW Fry Powder are used. Once fry are able to take freshly hatched baby brine shrimp, that becomes the staple. After the fry are larger enough to take finely crushed flake foods, Bug Bites color0enhancing flakes and Bug Bites spirulina flakes are used for one feeding each day, with BBS for the other. After fry are large enough, frozen blood worms can be chopped up very finely. These killifish do not have a cutting organ at their throat base to break up large foods, resulting in death when food that is too large is fed to them. Some Killi keepers use vegetable shredding scissors to cut up live or frozen foods so that their fish can enjoy small portions. Live Grindal worms, white worms, blood worms, tubifex worms, and African red worms are all highly recommended if healthy source can be found — and when prepared in very small portions as described.

COMMENTS & ADDITIONAL INFORMATION

Annual killis are a unique breeder’s fish. They will only live for a narrow window of time — 6-12 months. During that window, they must be bred intentionally in order to propagate the line. Nothobranchius guentheri are an excellent “gateway” annual killi, because their eggs need only dry for a period of 8 weeks (2 months) befre they are ready to wet / hatch. In this window, from August through October 2022 several batches of N. guentheri fry were “wetted” for hatching. In each case, lots of fry emerged at the outset. But with the first batch, water quality crashed due to over feeding in a small 2.5 gal tank. The second batch — submitted for BAP — was quite successful, hatched out in a floating flow-through fry tray. A third batch was wet, hatched, but basically dissappeared within several weeks. Finding the correct balance between under-feeding and over-feeding is a challenge with raising up killi fry. Most all serious Killi breeders use a suite of live foods suitable for these nano fish. I have only maintained vinegar eels and baby brine shrimp. I like using Bug Bites flakes becuse they are made using Black Soldier Fly larvae. I think that this may help killis. Once mature, as has been stated above, great caution must be taken with feeding foods that are simply too large for them to swallow. They cannot cut a blood worm with the back of their throat, and will be forced to swallow foods much larger than they can really effectively digest unless care is taken to prevent this. Same is true of Mysis or other small shellfish. On the other hand, they are voracious eaters and will suffer if meals are skipped.