Be careful with Plecos. Common Plecos hit 24". They have huge bioloads just like GF. As they mature they get very spiky. They prefer neutral to lower PH water with driftwood. Opposite of GF.
The main issue is when they get big, if they panic esp after lights out they may injure Fancies by accident.
A customer was furious. His big 10" Pleco freaked out and badly wounded his beloved 10yr old Ryukin one night. The Ryukin died.
The Pleco wasn't being aggressive, the GF just couldn't get out of the way.
I've had at least 3 customers tell me stories of Plecos injuring Fancies.
Just be aware. I don't think they should sell Plecos that hit 2 FEET to most people. Great fish , few people can house adults. Recommended tank is 150g.