When i added the loach, it had been going for 5 weeks...
I have upped the temperature, will see what happens.
Personally I Have only had 2 breakouts of Ich since i started keeping fish 4 years ago and none in the last 2 years I do not like the idea of using the salt method with tropical fish but that's me so I cannot help you with the salt thing.
Some people say garlic extract again I have never used it so cannot advise you, I would recommend you get a medication asap but as it has been mentioned before you have made a rod for your own back with putting fish in an un cycled tank, but for the moment it is a good idea to understand what you will be dealing with so here is the basics of Ich as I understand it:
"Ich" is the convenient way to refer to the organism Ichthyophthirius (sometimes Ichthyopthirius) multifilis. This parasite has three stages to its life cycle: trophont, tomont, and theront. The white spots on an infected fish are visible during the trophont phase of the cycle. The spots are actually scarring that occurs as the parasite burrows into the outer layer of the fish's skin. Beneath each white spot, the Ich is forming a tiny cyst in which it multiplies by cellular division. At this stage of the infection, the Ich is impervious to medication.
When the cysts mature, they burst and release thousands of the tomont stage cells into the water. The tomonts develop a slimy coat immediately after emerging from the infected fish, which allows each one to adhere to aquarium décor, substrate and even the glass walls of the tank. Once the encapsulation is complete, the organism begins a second stage of reproduction by further cellular division.
Finally, the Ich is released from the capsules in its theront phase. These theronts swim out in search of new host fishes and begin the cycle again. It is only during this free-swimming phase of the life cycle that medication is effective. Theront cells are not visible in the water.
So increasing your water temperature to a maximum of 30 degrees Celsius that will only increase the cycle of the parasite to the point that you can treat it with a medication the increased temperature does not in anyway actually kill the parasite.
Many different products are available to deal with Ich, but perhaps the most effective products are ones that contain the chemicals formalin and malachite green (sometimes called malachite blue or Victoria green). Both of these chemicals are highly toxic and in some areas, their sale is restricted. They are carcinogenic, so great care must be taken to wash any body part that is directly exposed to the medicine or treated water. Products such as Rid-Ich and Quick Cure are available as do most of the popular Fish treatment company's have an Ich treatment available in most aquarium shops. Also beware with fish like Loaches who have very small scales it is advisable to use half dose as the manufactures recommendation but you have been advised of this already.
Final bit of advice is see the full treatment through as just because you cant see the white spots it does not mean it has gone away, plus the tank sounds like its not cycled so you need to take the advice given to you in this thread and it also sounds like you have a tank size issue versus species namely the Clown loach as well which will only cause more ich as the loaches will get stressed
I do hope this helps you Regards onebto.