The 6-square deepwell microtiter plate was developed by Enzyscreen in 2014, together with Allison Bianchi from Amgen, specifically for the cultivation of CHO-cells. Since then, more than 30 research groups (mainly in the biopharmaceutical industry) have switched from 100 ml flasks to our 6-well plates, with the main advantage of easier automation and centrifugtion, but also the better mixing. The wells are not fully square, but have rounded corners, to prevent splashing, and limit shear forces to an acceptable degree. The conical bottom allows effective centrifugation at a low speed.

Preferably, an orbital shaker is used with a throw (shaking diameter) of 50 mm. In this way, both shear forces and splashing are minimal, because a relatively low shaking frequency can be used (150-180 rpm). See the first video below (180 rpm, slowed down 30 times).

Culture volumes between 25 ml and 35 ml are generally used, but some users have reported good results with culture volumes of 45 and 50 ml per well. If such high volumes are also possible for your cell line is a matter of testing in simple optimization experiments (see also: https://www.enzyscreen.com/article/cultivation-of-cho-and-hek-cells/

Shaking on a 25 mm shaker is also possible (at 180-225 rpm), but there is more tendency to mild splashing under these conditions (see video below; 225 rpm slowed down 30 times).

Under both conditions oxygen transfer rates  are in the range of 30-40 mmol O₂ l^-1 h^-1 (corresponding to k_La values of 150-200 h^-1).