Very eloquent :clap:it's a problem because these varieties of shrimp were created in the first place by very careful breeding to enhance a particular feature, color. You start with a basic wild Neocaridina shrimp and it is brown mostly, but with flecks of green here and yellow there and red someplace else. You start with a large group of that species and you separate out the ones that have more red and only let them breed with each other. Then every generation you separate out those that are redder than the others and only breed them together. Eventually you wind up with the Red Cherry Shrimp. You do the same process with those with more of a yellowish tint and after many generations you have what we call Yellow Shrimp.
They are both still Neocaridina however, so if you let a Red Cherry alone unsupervised with a bottle of whiskey on a Saturday night with a Yellow shrimp of appropriate gender, you will wind up with red/yellow cross babies. These will be perfectly fine shrimp mind you but their colors will be all mixed back together. You do not get an Orange Shrimp, you just get a brownish-greenish Neocaridina wild-looking shrimp. Which is what you started out with when this project began, making the whole thing pretty pointless, don't you think?
In answer to your specific question about CRS (Crystal Red Shrimp) and RCS (Red Cherry Shrimp) you can ply them with whiskey and Barry White albums all you want and attempts to crossbreed will be full of FAIL. CRS are a different species, Caridinia, from RCS (Neocaridina) and can no more breed together than a pig can with a pigeon.
They are both still Neocaridina however, so if you let a Red Cherry alone unsupervised with a bottle of whiskey on a Saturday night with a Yellow shrimp of appropriate gender, you will wind up with red/yellow cross babies.
Whenever you house color variations of the same species in the same tank, you are creating less desirable color mutations. If not corrected, the mixing will dilute colors and possibly revert to the muted wild markings. I know that there are multiple color variations of CRS (all red CRS, all white CRS) and RCS, and levels of 'quality' with respect to each. It is to maintain the depth, and complete markings, that segregation of specific stock is practiced. This is why you can find shrimp selling for hundreds of dollars, they have been selectively bred for specific marking. The same is true of dog breeds. If you're going to keep pure bred dogs, why mix multiple variations (breeds) and reduce the quality of your stock?Thanks to everyone who added their input on my question. You have given me a very good idea about the issues of crossbreeding shrimp. However i still have a question, what species (if any) are in deed crossbreedable and will prodice proper young, as apposed to those that will produce "wild" looking young?
This is true, but it is not so simple. There are yellow color variants, derived from CRS. Red Cherry shrimp have also branched into different colorations. That's why I prefer the combination of scientific names with common names, as much as possible, to eliminate the confusion created by the use of common names alone.1t I think we may be confusing the word "crossbreedable" with plain ol' regular breedable. Keep RCS with RCS, and yellows with yellows etc and they will make more of the same. That's what leads to growth in the hobby and profits (albeit small in most cases) for the breeder.
This is also a good practice to consider. Especially, if you ever plan on trading/selling shrimp to another. It is not fare to say you're selling a dog as a pure bred lab, when it's mixed with multiple other breeds.Do keep an eye on the resulting offspring though. To keep the strain strong you need to weed out those with weak or "off" color. Otherwise over time they will drift back to the original wild type or at best just look pale and faded, since they still have all of those genes available.