question

I think what you're saying is that the system drops to float earlier than you expect.

It will drop to float (i.e. sees battery as charged) when three criteria are met. Charged voltage, tail current and tail current or less for the charge detection period. Additionally if you have set a max absorption time, this will also cause the switch to float.

As the system switches to float, SOC is set to 100%.

Weather can cause low charge current causing false detection of fully charged when charging from solar. The cure is in the BMV: reduce tail current (as you've done), increase charged voltage to just below absorption voltage and increase charge detection period. If you have set a max absorption period, remove it. These settings, particularly charge detection period, are dependant on local conditions. Charge detection of 15 minutes or more is not unreasonable.

Hi @bunzeyda

In your system there are two types of 'Tail', one in the BMV, the other in the mppts. They serve different purposes, so don't confuse them.

The BMV's Tail is in '%', and decides when to sync to 100% SOC (considering Charged V and Detection time too). So it decides when the batts are fully charged, but you have to tell it how to decide. Like whether to sync under Absorb or Float. Chew this over thoroughly, the settings need to suit.

The MPPTs' Tail is in Amps and has nothing to do with the Adaptive (see the manual) algorithm. It's used to terminate Absorption phase, and will override both Fixed or Adaptive settings. It will use it's own Amps, but that can also include loads, so often not directly relevant to the battery. With DVCC (SCS) set to use the BMV, it's Amps will be used, so then relevant. A great feature. 0.5% (converted to Amps) set there is way too low, 3-4% more suited as a start point.

I cringe somewhat seeing 6x agm Batteries in parallel. This shouts Imbalance at me, and you'll need to set them up carefully for a long life. By all means come back with more questions, but please read and understand the manuals first.