What Species Are They?

went into a shop to get some "hong kong" plecs (the cold water ones) for my unheated tanks, as i was recomended not to put ottos into unheated tanks. i got four of them, three of them are mall and spotted and one is quite large, and stripped. are they different species? the small spotted ones were also in some of the tropical tanks as "butterfly plec" can anyone shed any light?

These fish are called Hillstream loaches, they are loaches no plecos despite petshops often selling them under names like "hong kong pleco". They need a rather specialised set up to thrive, and unless you tank has a lot of algae growing in it they will probably not last long as the vast majority of hillstream loaches are half starved by the time they end up in petshops and they do not take well to prepared foods- most hillstream loaches will only eat fresh algae growing on surfaces. They are sub-tropical fish and need a highly oxygenated and filtered tank, most common cause of death in these fish is either starvation or death from long term suffocation.
Keeping hillstream loaches;

http/www.loaches.com/species-index/beauf...a-kweichowensis

And a more indepth article on keeping them;

http/www.loaches.com/articles/hillstream...n-the-fast-lane

Basically, if you stick them in the average tropical or coldwater tank, they are unlikely to last long. Not meaning to lecture you or anything, but if you see a fish in a petshop and you don't know anything about it, don't buy it until you have thoroughly researched it first.
If you really want to keep these fish alive and help them thrive, you need to set up a sub tropical tank with powerful filtration, making it into a river type set up and invest in strong lighting to grow a lot of algae in the tank. There are many types of hillstream loaches, you appear to have two different types of hillstream loach, there is plenty of info on them on loaches.com and setting up the right sorts of habitats for them .

thanks for that, i did have one each in with my male bettas tanks but they dont get on so moved them to another tank where i had the other two, the water is maintained in this tank at 24oC and has very well filtered, and indeed has alot of algae. im amazed actualy that in the 24 hours ive had them, they have cleared alot of the algae from the glass.
i understand what you say about not buying a fish unless you research it first, its not normaly something i do, but i took them as i was recomended them for cooler water tanks.

They look gr8. Nice loaches.