Luc, I think I may have a scanner built that will suit the purposes. I populate my database every 5 minutes with the latest prices for the top 100 coins on market cap. I have millions of price changes recorded. So if I have this right, you would like an alert for any coins new price which is lower than the last lowest within a three day range. Correct? If the price meets the criterea send an alert. Correct? That can be done no problem although the alert would be SMS or email. There is an app to send the SMS messages for free. If this is what you require send me an email newcoinalerts@gmail.com and I will send you alink so you can test the system. Simple to use. I don't want to make the link public at the moment, but may do if you see merit in it.
Also thanks for the great videos.
Personally I just set alerts using Coinigy, because there are only a few coins that I really go big size on, so thats not alot of alerts to be setting. But in the slack chat room they have a Base Breaking scanner that they are working on.. I don't really use it, because what I'm doing right now is working fine for me. Honestly, between the stock market and the crypto market, I have plenty to trade in a day.