Posidina tradition

There are a few minor issues with this, the first being that its completion should have been mentioned in the Atlas forums where things are easier to keep track of.
Second, while you have based this on whistle up the wind, you have increased both the range and the target levels, so it seems that the effects at a given target level should be lesser- at the same time adapting the descriptions directly from whistle up teh wind doesn't match since a current at the same relative intensity will not do the same things- moving air, for example in ars magica is inherently fresh air, while moving water is not inherently cleaner and, given the fact that moving water tends to stir up settled material is likely to have the reverse effect.
Level 6 of whistle up the wind matches to chamber of spring breezes in base effect, which is one, while the level 9 effect (deflecting arrows) matches obliquely to circling winds of protection (base 3), though possibly a lesser effect. the level 12 effect propels a ship which by CrAu should be a base 2 if the ship has sail which is not specified... also the background feels a bit hinky, especially trying to define so many extra virtues and flaws, where I can only find one other ex miscelanea tradition which has even a required virtue, and that is piercing gaze, which is a minor general virtue, not a supernatural one.

Sorry for the delay. I had a rough time with being unemployed, and had to seriously scale back my time online.

I understand your concerns, and was thinking of scaling back the range to Touch.
The basic effect of cleaning a small pond wasn't because the waters become fresh, but more because the movement in the water causes the debris and impurities to be washed out of the pond. That is probably because English is a second language to me, and I do sometimes revert to direct translation instead of trying to find a more appropriate term in English.

i know you hate them, but the Beast Masters have 4 required Virtues and Flaws. Animal Ken is one of them...
The other Virtues are not required, and are a list of common Virtues. No one is required to have any of them.

And as I said, we can work on the guidelines together, this was just something I threw together, but I don't consider myself expert enough to balance new rules for Ars Magica.

If we switch range to touch, area being boundary (50 paces from the magus), then a target of 12 would be able to push a small boat, target of six would refresh stagnant water and muddy clear water. 9 would allow the slow drift of floating materials. 18 would create an undertow that requires a roll of 9+ on strength+swim to avoid being pulled under, which I think would put a 15 at a current strong enough to move a ship slowly or a small boat quickly, requiring a str+swim roll of 6 to avoid being pulled under. However this still doesn't address the major issue which is that of a required virtue of undine blood. Personally while I am willing to consider this ex miscellania tradition I am not thrilled by it and don't have any motivation to put in any great effort trying to save it.