We rent our house, reasons unimportant, but it’s a massive and beautiful thing in the Scottish countryside. We have 4 nature ponds. I’m from California but as the husband is Scottish I have lived in Scotland for nearly 10 years. Our house is on a castle estate and was once the Dowager House (where the castle’s “retired” generation“ used to live in “Downtown Abbey“ days. Amazing house.

Three of my ponds are made of stone (See bottom photo to get idea, ignore green water), including the bottom. No liners, no soil. They are part of a sort of garden feature that starts with a little pond the bigger and finally one about 4 feet pretty much all the way around and about 2.5 feet deep. I keep one water lily in the largest of the 3 ponds and it’s a happy plant, getting its first flower soon. We have a larger nature pond on the other side at the bottom of the garden and it’s a city of tadpoles. It’s about 10 feet wide4 feet across and 3 feet deep. It sit between a small part “island“ on its far side where we keep a small flower garden. On the near side is a raised garden made from stone taken from the 16th century castle where our landlords live. On the raised garden theres a walkway ending in three steps down to the water. This pond is very happy. I toss in a probiotic “bomb” twice a year that breaks down slowly and I have to solar aerating fountains, one on each end that make a relaxing noise. Scotland has very long summer days, sun up by 4am and sets around 10 or 11pm...my cats think this pond is paradise for summer naps and yes Scotland gets warm summers, it been about 75+ Fahrenheit Mo’s of this spring and summer

I’m not here ab the perfect pond though. Of my 4 nature ponds, ONE decided last year it wanted to be pea soup green. This is new, we had been here a few years with no problem, using a pet, wildlife, amphibian, and plant safe product to keep the water clear and the probiotic bombs in these ponds too.

Why on earth did the largest of the 3 connected stone bottom ponds go green? No algae, it was crystal clear when I cleaned it out in March for the summer. The previous summers the occasional from could be seen swimming along happily and I could see the frogs before but starting summer 2019, I couldn’t see a frog if I tried. I treated it with everything safe for all life form. No change. My water lily was happy, odd. Tested the water chemistry, all fine. I kept at it, no change

This year March was hot and sunny, even 80 degree days in Scotland. The pond was clear, I even took a photo. By the time April arrived, so had green soup. Chemistry still okay. Lily survived our very mild winter. I had started my green water treatment routine that I followed the previous summer, nope. I bought a stronger but still safe product, nope. Dosed again as directed, nope. Water hardness a bit off but not lethal and normal after a few we had a few days of rain.

I’m at a loss. I’ve even emailed the comp who’s products I’ve used. As we have deer, pheasants, frogs, water lilies, and other water plants I only trust companies proven safe with animals and amphibians.

id love suggestions. The product I use has a UV protection ingredient. I can’t run a UV light as Britain doesn’t have outdoor electricity outlets.

in working in the garden we discovered a fifth pond that is currently empty. We hadn’t noticed it as previous inhabitants filled it with branches from tree trimming. We’ve left it empty until we figure out what’s going on. A new nature pond will definitely have green water problems so I’ve been holding off over two summers now. we’ve thought about the 5th pond since moving in 4 years ago. We’re fortunate our landlord has given us free range to do as we like with both house and garden

HELP!

Thand, before and after photos attached, taken only one month apart believe or not

PHOTOS: Top taken April 2020 w/aerating plant Ranunculus, floats white flowers when grown

Bottom: July 2020 (powder on lily pads is a water treatment that blew a bit onto pads a bit

cari