I’ve noticed in several ponds i fish that sometimes there are weeds and mats on the surface one day and then a few days later it’s not there, it sinks.

 

Aside from wind, how often does this happen in ponds and small bodies of water 

I fish a lake that has Chara weeds. This year not as bad as last year. They grow to the surface and curl around, partially submerged. I think the weight of these plants make them sink eventually, along with wind and rain.

What you may be seeing are actually algae mats that rise off the bottom, mostly on sunny days due to oxygen production which “floats” them. On cloudy or rainy days, or at night, a lot of these mats end up sinking back down since they are no longer producing the trapped bubbles that caused them to rise initially. If so, this is very common in ponds, but will vary from pond to pond depending on amount and type of algae growth, treatments, etc.

 

Yes i think that’s it the algae.  

 

As this floats and sinks does it affect the fishing? are there are good rules of thumb to follow?

 

I also know there is one pond that i that has more of a grass on top and some times it sinks, and others it’s on top very strange 

 

 

1 hour ago, Jeffrey Walker said:

Yes i think that’s it the algae.  

 

As this floats and sinks does it affect the fishing? are there are good rules of thumb to follow?

 

I also know there is one pond that i that has more of a grass on top and some times it sinks, and others it’s on top very strange 

 

 

Doesn’t usually affect the fish, but can make presenting a bait to fish difficult at times. You often have to make short and specific casts or pitches. Or, wind will sometimes pile it up on downwind banks where you can fish weedless baits like frogs over these larger mats. 
 

The other weeds you mention might be a type of coontail which doesn’t really have roots, so it can move around a bit depending on weather (wind, rain).