Lee, we should like to welcome you i n the Parosphromenus project, if you could log-in once. Then your address is in our data-list and we could inform you about fellow aquarists in the UK.
But let me say the following here: What you report is the normal situation nearly everywhere. If the fish that you see in your local shop appear to be healthy with open fins and no meagre body, then you can buy some without doubts. But don’t put them in Paro-suited water at once. Begin with that tap water again, and change it within two weeks to the right water in small steps. In two weeks time it should In any case, you should prepare one or two Artemia breeding bottles so that you can have fresh naupliae every few days.
That the shop indicates these fish as P. spec. is a good sign. It means that they are conscious about the fact that they are no “deissneri”, and that the exporter in south-east Asia is conscious about this as well. Normally, the most wild Paros sold in the international fish trade are nowadays from Sumatra and either the so-calles spec. blue-line or the so-calles spec. Sentang, very nice fish but not scientifically described hitherto. And normally the offered fish are not species-mixed.
Look to get males and females. Probably the male fish don’t display bright colours in the trade’s tanks (why should they, without quietness and caves in a bad milieu?), but any markings in the fins would indicate males. The dorsal fins are normally more pointed than those of the females, which must be clear and transparent.
I shall write to you a private mail after you have logged-in; before it is impossible.