Thanks for the input guys, I've got them under some florescents and have filled the pots with more media, fingers crossed these guys will pick up. After doing some research the do look like Hylocereus seedlings. There are no spikes visible but I've had some mystery cactus mix seedlings that started off like these Hylocereus and later developed the cactus shape & spines.
Some pix of Hylocereus seedlings I found:
http://www.vivapitaya.com/seed_files/seedlings.jpg" onclick="window.open(this.href);return false;
https://c2.staticflickr.com/8/7193/6822 ... f20e_z.jpg" onclick="window.open(this.href);return false;
Although you can't believe everything you read on the web.
Thanks again for the advice, you guys are great! It's nice having somewhere where I can indulge my cactus fetish
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