well if there is a risk of total loss due to the burn and its not stopping you pretty much will have to flush your plants in order to try and stop it... i would flush with a heavy water only watering and see if it slows or stops, if it stops you should be fine, your plants may be shocked for a bit but will recover (would help if you posted pics of entire plants) if it only slows or doesnt slow at all you may need to change soil and try to flush the root ball itself. this is always risky but can help a plant that you think might not make it and you feel its worth the risk.