Yes, but only via the external signal generator GC-SIGNAL. There you can set how the lamp should light up in 1% increments. The GC-SIGNAL has many other functions that can improve the culture result.

No, it is quite possible that certain plants or varieties respond well to a different mixing ratio. For example, we have customers who generally work with 100% flowering mode but only 80% growth mode during flowering. However, we do not have a database with information on which mixing ratio is best. Experimenting is part being gardener.

This is also purely for technical reasons. We would like to have installed stepless dimmers everywhere. However, implementing a good, stepless dimmer with the digital control signal is challenging.

This is purely for technical reasons. Since the GCx-16 and GCx-25 are also used in larger, professional systems, they must be controllable by an external signal generator. This required the installation of a minicomputer, which makes direct (analog) control of the drivers impossible, as with the GCx-4 and GCx-9.

No, see above.

Basically, ONLY the growth mode is used at first. The flowering mode is SWITCHED ON (not INSTEAD of the growth mode). The ideal light for flowering is when the growth and flowering modes are equally bright. Allowing ONLY the flowering mode to light up would be wrong, as the light is TOO red and there is no UV light. With the GCx-4 and GCx-9, it works like this: For very small plants, it is sufficient to reduce the growth mode to 10% or 20%. As the plants grow larger, the growth mode is gradually increased. Larger plants require more energy. At the end of the growth phase, the growth mode should be set to 100%. At the beginning of the flowering phase, the growth mode is reduced again to 50%. At the same time, the flowering mode is increased to 50%. During the flowering phase, both settings are increased synchronously: growth mode and flowering mode each to 60%, and so on. After ⅔ of the flowering phase at the latest, both mode controls should be set to 100% so that the plant receives the maximum light output. It works similarly for the GCx-16 and GCx-25: basically, the same as for the GCx-4 and GCx-9, but there is only one control and one toggle switch. During the growth phase, the toggle switch must be in position 1. This only controls the growth mode. At the start of the flowering phase, the toggle switch must be switched to position 2 (both parts now light up), and the control should be set back to 50%.