So !
I will not get into the details for reasons of identification but basically :
I have to brew a simple SMASH beer for 70H for an experiment, at which point I am supposed to throw it away. Which I do... Mostly.
The mash isn't an issue (had a foaming once because I kept it a 50°C) for ages because Lab techs kept me busy at the worse time), and it ends up at 1053-1053.
After a fermentation of 70 hours I reach about 40 to 45% reduction which translates to a density of 1025-1026. Nothing surprising with SF-04 so far. The fermentation of these 70 hours is thermally regulated to have a heat spike that follows the activity of the yeast thanks to a software that correlates CO-2 production, so the bachelor's cooled down to 25 degrees where the yeast is added and then it is fermented with a baseline of 20 degrees all the way up to 24 at peak activity, then back to 20 degrees and I let it rise up to 24 before I throw it away.
The thing is I don't really throw it away. I keep around 5 to 5.5 liters of it, can I date something that I wasn't used to. Thing is at this point I have already brewed beers of that kind with that yeast and I would usually have thrown it in a bucket cleaned carefully, kept it in the shade and waited for ages.
Only had to throw away two batches because during the heat wave they cooked - the buckets are opaque but not thick enough to be truly protective of the light and they were kept on a table which actually does get some sun in the morning, so when the temperatures reached 38 degrees indoors... They actually managed to reach 42. The yeast, understandably, stressed the fuck out and made a fuckton of VDK, before fucking dying.
However I have three batches the latest of which is three weeks old, that I have kept in the shade which have been fermenting between 20 and 25 degrees so far.
Now the thing is each and every single one of these batches, is one that I have reintroduced sugar to in the form of honey until they reached about 1036 gravity - the goal was to get them out of the bucket at around 7 degrees ABV, at which point I could give them just a little bit more honey diluted into a syrup pour it into bottles and voilà !
However after a week they all went down from 1036 to 1027-1028… which is not exactly strange because the concentration of alcohol is rising and the temperatures are not exactly ideal. A week later they go down to 1026 - two of them have done at least. The latest one however another week later has only gone down to 1024.
The questions are :
Am I stuck ?
And if I am, what can I do ?
Would it simply work to do a sort of second brew without adding any more sugar by just schlucking it in a bucket I either at ambient or in the fridge, and then add some honey before bottling ?
Should I use another mead yeast for a second brew like that, making a Meadeer ? Or Beeread ?
More infor :
I have access to fridge I can't control the temperature of but I can know the temperature of the exactly.
All three batches have been sweetened with honey, the same money for all three beers and the beer itself is the same for all three - a smash with 20 EBC malt and Perl hops.
I have access to urea and phosphate nutrient blend for yeast, and I have attempted to add a few RAMs to the latest bench just to see if it produces the difference but it is not old enough to show it.
I just shook them around a bit slowly without opening the pots to try and get the SF04 to resuspend a bit.
I am certain that I still have brewing activity because I still have bubbles in my bubblers, and that the lids of the buckets are buckling under the pressure.
I am using an optical system for the follow-up of the density but I have more precise lab equipment to follow up the alcohol concentrations, C02 production, and density, but only for the first 70 hours of the initial fermentation.