My 7000L QT pond had some terrible green water and since I am not very mobile at this stage I had little time to check out the UV (small UV on pond in full sun)

I had a 250ml bottle of TetraPond AlgoRem and decided to give it a try ( I hate adding funny things to the pond). This bottle only treats 5000L of pond water and my QT is 7000L so I had little hope for it to work at all.

I added 200g of clay to the pond and over about an hour period empied the TetraPond bottle into the pond. This was 5pm yesterday. This morning at 7 I went outside and to my total surprise found a crystal clear pond. Never had this clarity before

Tetrapond products work very well but are quite expensive...

Tetra is excellent but expensive when it comes to large ponds