AS very long term a filtration engr. (also worked indirectly for Parker's 'other' filtration divisions)............

Although 2GPH is an 'adequate system', you're MUCH better off doing the filtration through a 'high capacity' (3 gallons per Minute /100 gal. tank!!!) through a coarse filter ~15µM (nominal rating) that is totally independent on the fuel delivery system: tank --> 3GPM (Walbro, etc. constant duty 12vdc transfer pump ---> ~15µM filter ----> tank.
Such 'resinated paper filters' used for 'fuels' are quite 'crude' in manufacture and do not have a 'precise' removal rating BUT will have 'many' capture sites within the 'media' at well below the µM 'rating'; as an estimate a 15µM will remove (maybe) 5-10% of .5-1µM particles .... per tank 'turnover' ... recirculate the tank (turnover) 10-20 times and you are approaching an average 'residence' of .5-1µM particle fuel - absolutely 'crystal clear'.

Where a 'high capacity turnover system' is beneficial is RAPID recovery of clean fuel in case you have a 'slug' of particles break loose from the tank walls wherein a 3 GPM/100 gal. system you will 'restore' back to an acceptable level particles in about 30 minutes; the Racor 'recirc' system @ 2gph (0.003 GPM) will take almost ~2 days !!!!!!

The advantage to 'any' configuration 'recirculation polishing' system is that it will constantly remove the 'seed particles' which 'grow' or agglomerate into larger and larger particles ... and 'crud'.
"Polishing" will NOT clean a dirty tank ... a tank that has its walls fouled with massive depositions microorganisms, chiefly fungals (eg. Cladosporium Resinae ... 'resin formers'). A recirculation polishing system removes/captures these particles 'before' they 'grow'/agglomerate and attach to the tank walls, etc.

With a DIY system made from industry common components (2.5 or 2.75"Ø X 10" long filters, etc.) you arent 'locked' into proprietary configurations .... and costs.
A std melt-blown polypropylene 'depth type' filter @ 10-15µM will be ~$10-15 ea.
A industry std steel filter housing for 2.5 or 2.75"Ø X 10" length std industrial filters will be ~$80 - $120 ea.
I use a Walbro #FRB-13.2 .... dont have the price handy.

hope this helps