I have a few old opinions about this subject...and a new one. I think I even expressed them in a long winded response a few months ago...but in fairness to the original poster, I will repeat:
I believe:
The snubnose effect is 100% environmental and avoidable. It occurs when a hatching fry damages ...

Be aware, however, that the Hypancistrus furunculus; L199 gets considerably bigger than a zebra. Don't expect spawns from L199 of adult zebra size. My furunculus were nearly 4" before they were mature enough.
Kevin Korotev
Milwaukee, WI , USA

Yup. They're a true/bonafide/proven/bonded pair. I can't blame you for doubting that though.

Here's the truth, as I wrote it on AQUABID:
*************
You are bidding on a proven adult pair of Hypancistrus zebra. Both fish are easily 3" and have been BREEDING TOGETHER since late last summer. I ...

I have HEARD (and it did not necessarily refer to Loricaridae) that the egg shell can be harder (thicker) in harder water, softer (thinner) in softer. In addition to the softness of the Rio Xingu, we might want to also consider the pH. Slighty ACID water (if also soft) will deteriorate a shell ...

It seems from the time stamps on your posts that most of you are on the other side of the world from me. This is unfortunate because I believe I would like to pick up the gauntlet on this "Breed the Bulldogs" challenge.

I suspect young adult snub-nose zebras may be hard to find, but if any of you ...

The more I think about it, the more convinced I become that the snub-nose effect is environmental. I decided to (without any prejudice) discuss the matter with my own personal pleco guru: Janne Ekstrom. If you've ever been to Planet Catfish, you'll recognize the name. Here is his unedited response ...

Thank you all for the warm welcome, both here and in my personal inbox.
The number of people who read the article I wrote so many years ago now (it seems) continues to amaze me. I should probably go find it again myself and see how many foolish things I said.

It seems a standard habit to pull the ...

I have been brought into this discussion of the snub-nose F1 H. zebra through my association with a couple of the participants in this thread.
It is a fascinating debate and one that, in my opinion, is yet to be satisfactorily answered.

I first spawned H. zebra a few years ago and was so ...

I have been brought into this discussion of the snub-nose F1 H. zebra through my association with a couple of the participants in this thread.
It is a fascinating debate and one that, in my opinion, is yet to be satisfactorily answered.

I first spawned H. zebra a few years ago and was so enthralled ...