Algae Eater?

I'm thinking about what fish I'd like to add to my aquarium in the future and I've been using the community creator to get an idea.  We've got 6 guppies and 6 harlequin rasboras ( and 4 amano shrimp) I'd like some neons, barbs etc but I'm wondering if anyone suggests getting an algae eater? I understand we can't have corys or loaches due to our gravel substrate which isn't perfectly smooth gravel, but are there other algae eating fish anyone could suggest or advise? Currently have a 125 litre fluval roma with a fluval u3 filter. Thanks

Strictly speaking, you don't need a fish to eat algae, if you get some you should find out the cause and solve that.
A bristlenose plec would fit in your tank, but they do poo a huge amount for the size of them.
Alternatives are shrimps and snails, if you don't mind creatures like that. Nerite snails are wonderful algae eaters, though they don't eat all types of algae. I'm not sure about shrimps and barbs, though they would be fine with harlequins, guppies and tetras. Cherry shrimps and the larger amano shrimps (in the fish profiles as japonica shrimps) would eat algae. But wait till last for both shrimps and snails as they are more sensitive to water conditions than fish, and need the tank to be totally stable before adding any.
Live plants would also help with algae by using the nutrients plants like before algae gets a chance.