Hi guys,

I have a half barrel pond in my garden, which over the last couple of years I have done nothing to. I have just let it be like its own ecosystem. I will add water with the hose from time to time, but thats about it. I have about one plant in there......Here's the thing though. Last year Pacific Tree frogs laid eggs there, and then I got tadpoles, and now I have more frogs. Mating season just started again this year and this morning I found a new batch of frog eggs. I think there is probably a bunch of sludge in this pond - I have a couple of snails in there to keep the algae down but the water is pretty murky. I want to go in today and completely change the water and clean out the pond. Is there a product I can get at a regular pet store to treat the water for the chlorine? Every time I start looking at these products I worry that they can only be used if there is a filtration system. Or sometimes the directions apply to much larger ponds and I can't really calculate how much to put in this half barrel size (I don't even know how many gallons it holds)

Can someone recommend a product I can get at the pet store to use in this pond?