It is well known that most Be stars are photometric long-term variables, and that at least two characteristic behaviours can be recognized when simultaneous photometry and optical spectroscopy are available: positive and inverse (negative) correlation between the Balmer emission strengths and the stellar brightness (Harmanec, 1983). Indeed, a positive correlation has been observed in several Be stars as their Hα emission gets stronger when their photometric V magnitude increases:
Harmanec, P., 1983, Hvar Observatory Bulletin, 7, 55
Juza, K., et al, Astrononmy and Astrophysics Suppl., Vol. 107, p.403-411 (1994)
Koubsky et al., Astronomy and Astrophysics, v.328, p.551-564 (1997)
http://www.bav-astro.de/rb/rb2011-1/5.pdfhttp://www.bav-astro.de/rb/rb2014-2/89.pdfhttp://www.bav-astro.de/rb/rb2012-1/20.pdfhttps://konkoly.hu/pub/ibvs/6101/6109.pdfObviously this is also applicable for pi Aqr. The attached plot (top) shows the Hα EW developement from JD 2456868 (2014/07/29). The plot bottom shows simultaneous V data (AAVSO data base) versus Hα EW (BeSS spectra) from Oct. 2014 to Oct. 2021.

- Vmag versus Halpha EW.png (86.38 KiB) Viewed 3342 times
The current visibility of pi Aqr invites to take spectra in order to complete the correlation.
Ernst Pollmann