Hi I breed XIP long term.
Here is an excerpt of an article I wrote for a national association newsletter on the subject.

I had been looking at trying to re-introduce Rivulus xiphidius back into my fish list for some time now. After chasing this species for many months from one end of the globe to the other I eventually found a chap in Spain who was willing to help me with my plight. It was the begining of August when I first made initial contact with my fellow killifish enthusiast. He had quite a few pairs at the time along with some Rivulus speciosus F1 which I also acquired.
The weather in Spain was too warm at that time to even contemplate sending fish so I had to wait until September for the transfer to proceed.
I was contacted again early September to inform me that he was ready to get the operation underway and he was dispatching four pair of Rivulus xiphidius Crique Boulanger and one pair of Rivulus speciosus PCCC 08/7 (f1).
The fish were being sent via the Spanish postal service Correos and were being sent in express fashion (Urgente),(Sat 12th Sept) with an informed delivery time of 3-6 days for UK delivery. I duly thanked the guy for all his help and correspondence in helping to re-attain this beautiful South American species.
The days went by and I waited and waited, still no sign of a package. I used the Spanish tracking code he gave me so I was able to assertain that the consignment had left Spain on the Monday (14th Sept). So I knew they were in transit. Unfortunately I couldn't track the parcel any further as Royal Mail's website doesn't track incoming International mail. So I'd just have to wait it out. Then a bit of bad news in the form of sporadic postal strikes hit home that I may never ever see the package let alone the thought of ever getting the fish to these shores alive. Just my luck. Again I waited. A week went by, I'd been rushing home from work each day discarding the opportunity of a quite a few hours overtime. Still nothing.
After seven whole days I began to loose the faith. They'll all be dead by now I would constantly inform the missus. Another week passed and by this time I was looking to re-start my search for XIP and the prospect of shelling out another couple of hundred pounds was not an exciting prospect.
Then on Saturday the 26th of September I arrived home from work at 11am to be informed by my wife that my parcel had eventually arrived and she had placed them on top of a tank to warm a little.
At least they were here but in all likelihood they'd be dead.
As the wife left for work, I was just about to make myself a cup of coffee when curiosity got the better of me and I ripped open the box.....
The box was just a flimsy standard cardboard mailing box with the usual stamps and stickers around it. Internally there were copious amounts of shredded paper and filter floss. Devoid of the usual polystyrene box, heatpacks and heavy internal insulation that we are so used to seeing I didn't hold out much hope of any sign of life.


Evidence of my frantic box opening techniques

As I foraged for the contents (fish bags) I managed to extract the first of such. A couple of Kordon Breathable bags no bigger than a couple of golf balls tied together at the top with elastic bands. No air in these bags (not needed) You can imagine my excitment as the contents of the bags started to shoot about in frantic fashion as they were exposed to the light. (of which they had not seen for two weeks) On closer inspection they were pretty under nourished but remarkably they were in pretty fine fettle considering. The bag was very cold so I wasted no time in floating it in a pre set up tank.
I extracted four more pairs of kordon bags from the mailing box, each time fish were thrashing about within, again the bags were very cold (around 56'F)
All the bags were now floating in a tank of warm aquarium water.
I mulled around for an hour or so as the temps were equalising (finally got that cup of Latte) contemplating what the next stage would entail and how I wouldn't want to muck things up having got this far. Getting the fish from bags to tank without any mishaps was now my uppermost primary concern.
I needed to test the water in one of the bags. I utilised a small show tank and carefully cut open one of the bags with a XIP male in and tiped the contents into the small vessel. The pH was 6.8 which wasn't too bad.
The TDS was 195ppm (11dKH) which again was survivable, but the chill might have affected them.
I managed to get a main tank to near as poss to the bag conditions and using a drip process I set about acclimatising all the fish to this.
After a couple of hours messing about the fish were ready for their new homes. The time of release was nigh. I carefully placed pair after pair into
small margarine tubs and covered them as Rivulus species are renowned pole vaulters. I placed the tubs into their respective tanks and removed the lids and then slowly submerged the tub until the fish vacated.
They were all now in and what's more they all were alive.
I now left them to their own devices for a couple of hours to settle in the darkened tanks.
I knew the fish were malnourished so I administered small amounts of newly hatched Brineshrimp and Grindalworm for them to forage on when they were ready. The females were the first off the mark and tucked into the food which they sorely lacked. The males were being their usual selves, as seems to be the norm in killifish feeding habits, initially letting the females get in there first and whenever they feel safe, then the males would join the fray, kicking the females to one side.
So everything is well at present, although the water conditions are nowhere near what they should be at the moment from a breeding standpoint. This will have to be addressed over the coming weeks.
For now I'm just glad that they are all safe and feeding.
Who would have thought that such a warm water killi could survive such a long transit time, in such flimsy packaging and plunging UK night-time temperatures......Amazing.





This article is about a year old and is a follow up to an original on breeding XIP.