When it comes to time, 15-20 minutes in warm water is enough for chia seeds to increase their size. Although size depends on the type of chia seeds, because not all type chia seeds grow about 9-15 times! Water:chia seeds ratio of 5:1 should be at-least maintained for a good result.ou should soak it till it forms a paste/gel like consistency and it would take at least 2-3 hours, though this website claims under ten minutes (time might vary depending on the batch of the seeds). You could also soak it in any juice or fruit extract as well.