I am not sure what sheet algae is, is it the same as string algae? I have had string algae several times over the years. I took apart my entire pond and scrubbed every flat surface. Then reassembled and kept debrie from falling into it as light as possible with daily cleanings with a net. Only takes a minutes when I feed my fish and helps a great deal. My pond is under a wheeping cherry and gets much leaves and blooming petal fall. Last fall I covered it with a net as soon as leaves began to fall, and kept it covered with the net all winter as I get a great deal of winter fall/blow into it. The net reduced it by ten fold...I will never enter another fall/winter without netting it again. Is a net an option? Once you rid the pond of the algae, use barley straw, it comes in either sheets you can slide under plants or rocks or in pellet form. I liked the pellet form best. If it is string algae, hand removel is about the only way I know of to remove it or so I have been told. And it will continue to regrow as fast as you remove it if you do not find and fix the source. I use the barley and a NET during times of falling leaves and I have not had string algae in about five years now...knock on wood..there is not much worse as a pond owner...good luck!

This is very normal. It's abnormal when it doesn't happen. Simple forum type answer is to add a UV filter. Long answer It's not specifically related to the goldfish. The fish do produce ammonia which algae uses to grow, but and this is a very important but, do not jump to the conclusion like virtually everyone does that the algae wouldn't grow if the fish are removed. It would probably grow less fast, but you'd still have the exact same problem. It's the same with sunlight. Algae grows slower in shade but still grows. To most people it doesn't really matter if there is 10,20% less algae, it's still too much. The other important thing to understand is in ponds we break algae into 2 general classes. 1. Green Water Algae, aka Micro Algae Micro just means small. This type turns water green. Meaning if you put pond water into clear water glass and hold it up to the sun the water has a green tint. Generally pond owners will say something like "I can see the bottom" or "I can't see the bottom very well" or "I can't see my hand when it's 6" deep" to describe how green the water is. These green water algae is a single cell algae that is so small it stays suspended in the water. Although these cells will clump together into larger balls and then sink eventually, but new cells will replace those. Also called suspended algae. 2. String Algae, aka Macro Algae Macro just means big. String algae is an unfortunate term because it's only one type of macro algae, but string algae is the term most often used in forums. There are many species of these kinds of algae. These are more like plants, you can touch them, pull it out, etc. Your description, which is common, covers both kinds. It's important to know which kind because the remedies are very different. The string algae type stuff generally grows on the pond walls, rocks, pipes. Some people seeing this say my pond is green even though the water is clear because they see the green stuff growing on the pond walls. You said It happens both in the pond itself, hosing and the waterfall. That describes macro algae which grows on things. But you also say can no longer see the fish which sounds like green water algae (micro algae). Micro algae does clump and sink and so the pond bottom, hoses etc, can get covered in a kind of green dust. To most people that could appear to be algae growing on those objects. You also said green scum. This is a term we use to describe a green film floating on the water surface. It can be very dense, almost like green paint floating on the water. This is a less common algae but could lead you to say you can no longer see the fish. So it's kind of important to narrow your description. Many people don't like algae and so like to use terms like "scum" just as a way to insult the algae. But this type of thing will only generate bad advice and make your life much more complex. Besides, algae don't read forums so they won't be insulted at all. But if your algae actually is scum then that's an important clue. The time frame you're describing also sounds like micro algae. New water, couple of weeks (2-4) and the water turns green. The most effective fix for green water (micro) algae is a UV filter. These are pretty cheap to buy and run and are 100% effective in removing green water (micro) algae in 3-7 days. It is so effective that the test for knowing if you have it sized and installed correctly is the color of the water. If there is any green tint at all it isn't sized or installed correctly. They're not hard to install, but unfortunately many people don't seem to like any kind of detail. They plug them in and if it doesn't work give up and start trying the many "fixes" that don't work. Such is the world. After the water is cleared you will very likely get a few kinds of macro algae. Interesting when this happens you can most likely turn off the UV and you may never need it again except may in the spring depending on your climate. Macro algae produces a chemical that kills micro algae. But micro algae also produce a chemical to kill macro algae. A war. The UV filter kills the micro algae and so their chemical goes away allowing macro algae to grow. Macro algae can be controlled by chemicals you buy, but I'm not a fan of those. Lots of issues, but is possible. Much easier to remove macro algae by hand. Like weeding the garden or mowing the lawn. Emptying the water and refilling is the most difficult way to deal with algae. You will often read in forums people saying "you're starting over" because it's widely believed ponds clear on their own given time, but most people don't know why. It's because of the chemicals produced by macro algae. Another effective when to deal with green water algae is to have a constant water drip into the pond. This is tricky in small ponds (100-200 gals) and almost impossible in most pre-form ponds because an overflow is needed. Here's a video that describes the system.

The suspended algae might or might not be caused by the fertilizer. Sometimes there is just the right amount of nutrients and light in a pond to make it go green. This is especially true of new ponds and ponds that have just been through a spring cleanout. I just put a new liner in my pond this spring, resulting in thick pea soup algae. I struggled with it for weeks, fussing and fretting about the fact that my pond is on a tour this weekend and I didn't want my guests and potential new ponders to be turned off by the nasty looking water. Finally, even though I'm not an advocate of putting additives in the pond, I bought a product called "Eco-Floc" and added it to the water. Within minutes, I coudl see the suspended particles binding together. To avoid having this stuff go to my filter, where it would rot and cause another algae bloom, I wrapped quilt batting around my skimmer mat to catch it. I had to rinse it out every couple of hours that first day, but the pond cleared up completely overnight. And to keep it clear, I bought a U.V. Clarifier. I know that's a dirty word to some, but I like to see my fish. The water is now gin clear and I'm ready for the tour.

<I don't see tomatoes as having as distinct a "veg" and "flower" stage > It isn't a single stage, it is a series of cycles that alternate back and forth as the plant grows. How obvious to the eye those distinct cycles may be is relative to experience and degree of close monitoring. In other words, obvious IF one knows what to look for. But while each plant has a wide degree of potential depending on the growing conditions provided, there are very different potentials between determinates and indeterminates. <Dave what type of stress would cause that? > That's the problem. It can be many things or a combo of things and can be difficult to ID. Basically anything that threatens its survival (from the plant's POV) and indoors is an artificial environment for the plants so difficult to make 'normal'. The obvious ones are root bound, pests, disease, excess watering or markedly inconsistent watering, excess nutrients. The less obvious ones are poorly draining or compacted soil, root damage, ambient air temps (too warm or too many extreme changes), artificial light that isn't full spectrum, lack of sufficient air circulation that allows for stagnant air to develop, etc. Dave