I am super new here so sorry if I am posting this in the wrong spot.

I am on Telus (a ISP located in Western Canada) they are providing GPON Service with a SFP+ module. Lots of network savvy folks have been documenting there experiences all over. More info about the Nokia SFP+ module (which is provided by the ISP) is documented on this DSL Reports post https://www.dslreports.com/forum/r32052 ... FP-install.

However, the SFP+ module only syncs at 2.5G and the router I am using has 1G and 10G support only. I am attempting to use the CRS305-1G-4S+in to connect with the Telus network via SFP+ at 2.5G and then connect to my router at 10G so I can get more than 1G speeds.

Anyone have tips on how I could achieve this? Thus far, I have disabled all speeds except 2.5G on auto negotiation on that port. However, I can only force 1G or 10G on the switch. When I do this it does not seem to connect with the SFP+ module. Additionally, if there is any information I can provide please let me know.

Firstly, the CRS is not a router, it is a switch by design and not sure you are going to get your full speed unless in a switched config.
Secondly, IIRC, Mikrotikdoes not support GPoN SFP interfaces, so my suggestion will be:
Connect the GPoN fiber to the ISP supplied Nokia, configure Nokia in a "Bridge" mode.
Then connect your router to the Nokia device and finally your CRS to your router as access switch

Secondly, IIRC, Mikrotikdoes not support GPoN SFP interfaces, so my suggestion will be:

@CZFan
RouterOS v 6.47.1 now provides support for GPON running in SFP(+) Cages ... this has been tested on the RB4011 using the HUAWEI MA5671A as evidenced in the following post.

@browntrch ,,,, MikroTik SFP and SFP+ cannot sync at 2.5 Gbps... only @ 1 Gbps or 10 Gbps.

@browntrch ,,,, MikroTik SFP and SFP+ cannot sync at 2.5 Gbps... only @ 1 Gbps or 10 Gbps.
[/quote]
I wanted to reopen the tread and ask if there are updates: Can SFP+ sync at 2.5 Gbps with Gpon module ? Thx

Same here.
I have Google Fiber 2.5Gbps service and they provide a sfp+ fiber optic gpon that's normally inserted into their router, but I've taken that out and I have it inside the sfp+ port of a mikrotik rb5009 router.

The rb5009 sfp+ port seems to only be able to negotiate a connection at 1G, and not 2.5G.
I haven't found a way to force it to sync at 2.5G. But otherwise it works great, only at 1G speeds.