This template should be transcluded as {{WikiProject Fishes}} and not substituted {{subst:}} because it employs conditional code. Transclusion also allows easy updating of all the WikiProject's talk pages without having to edit thousands of pages individually. For examples of how the template will appear under various parameter scenarios, please see Template:WikiProject Fishes/testcases.

A common initial configuration for the template includes the following basic parameters:

{{WikiProject Fishes|class=|importance=|needs-photo=|imagedetails=|in=|unref=}}

The template also employs several optional data field parameters as described below. The full syntax is as follows:

{{WikiProject Fishes
|class=
|importance=
|attention=
|needs-infobox=
|past-selected-fish=
|past-selected-picture=
|needs-photo=
|imagedetails=
|in=
|unref=
|peer-review=
|old-peer-review=
|category=
|listas=
}}

• class: FA, A, GA, B, C, Start, Stub, FL, List, Cat, Dab, File, Portal, Project, Template, and blank (#default), and NA. NA is "non article", which includes redirects and user talk pages. Some of the option descriptions may be found at WikiProject Fishes/Quality scale.
• importance: Top, High, Mid, Low, NA, and blank (#default). Some of the option descriptions may be found at WikiProject Fishes/Importance scale.
• needs-photo: Answer yes to request that a photograph, map, drawing, diagram, equation, or other image be added to the page. Leave blank or delete if not.
• in: Used in conjunction with the needs-photo=yes parameter to place the image request into a specific location, such as a Fishes county. For example, "in=Los Angeles County, California" will place the article talk page into Category:Wikipedia requested photographs in Los Angeles County, California. Leave blank or delete if not.
• imagedetails: This free-form parameter can be used in conjunction with the needs-photo parameter to add specific details about the images being requested. For example, |imagedetails=Please add an action shot to this article. will add the following to the template display: "An editor suggests the following: Please add a live-action shot to this sports article."
• unref: Answer yes if the page needs additional references or inline citations. Leave blank or delete if not.
• past-selected-fish: Enter Month Year (e.g., "past-selected-fish=June 2006") if the fish article previously was selected as the Fishes Portal's fish of the month. Leave blank or delete if not.
• past-selected-picture: Enter Month Year (e.g., "past-selected-picture=March 2008") if the image previously was selected as the Fishes Portal's picture of the month. Leave blank or delete if not.
• attention: Answer yes if the page needs immediate attention. Leave blank or delete if not.
• needs-infobox: Answer yes if the page needs an infobox. Leave blank or delete if not.
• category – set |category=no if, and only if, a banner is being used for demonstration or testing purposes, to prevent unnecessary or undesirable categorization. Otherwise, omit this parameter.
• listas – This parameter, which is the equivalent of the DEFAULTSORT sortkey that should be placed on all biographical articles, is a sortkey for the article talk page (e.g. for given name surname, use |listas=Surname, given name so that the talk page will show up in the S's and not the g's of the various assessment and administrative categories). This is important because it is one source used by those who set DEFAULTSORT on the article; consider also setting the DEFAULTSORT for the article when setting this parameter. For more information about this, please see Wikipedia:Categorization of people § Ordering names in a category.
  If the article is using {{WikiProject banner shell}} then it is preferable to add |listas= to that template instead of a project banner template. Putting the parameter on more than one template is not required.

• The parameters |needs-image=, |image-needed= and |photo-needed= are recognised as aliases for |needs-photo=. If more than one is present, the order of precedence, from highest to lowest, is: |needs-photo= → |needs-image= → |image-needed= → |photo-needed= . Parameters with lower precedence are ignored.

To avoid needlessly cluttering up talk pages, it is usually appropriate to remove any unused parameters from the template.