How to prevent algae formation in basin pipe

bathroompipe

In my house, I have a basin, the pipe of which is causing problems.

Background:

The pipe of this basin is connected to the same drain as the washing machine drain pipe. As a result, when the machine drains away water, due to the huge speed of water from the machine pipe, the water overflows up from the basin pipe joint. In order to fix this, I've fixed the joint with plaster of Paris, and now, water no longer comes put from the joint. But on the other hand, in order to remove the pipe, I have to literally break the plaster of Paris.

The Problem:

I'm facing a problem of algae formation in this pipe. It is algae, and not dirt, because it's forming over the mouth in the basin as well. But it is relatively easy to remove the algae from the mouth, than from the pipe.

I have already tried treating with acid, drain cleaners, and also the youtube remedies of using baking powder, vinegar and followed by boiling water. But none of the methods are able to actually remove the algae from the sides of the pipe. In the picture below, the dark parts are the algae, while the white parts are free from algae.

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I've finally decided to take off the pipe tomorrow and clean it properly by hitting it against the wall in bathroom (the jerking cleans off most of the algae).

Is there anything that I can do on a periodic basis, which will prevent algae formation? It's very difficult to go through the above procedure again and again.

Best Answer

Two things spring to mind. Algae are green plants, so lack of sunlight is an effective deterrent. Switching that translucent white pipe out for an opaque black one or going crazy with the duct tape should help. (Ideally a smoother pipe, Ed Beal style.)

Second, potassium permanganate (KMNo4) is very effective against algae. I don't see how you'd get it to stand in the pipe long enough to do anything though. It's typically sold in either pool/spa supply houses or aquarium dealers, usually under some sort of brand name. I can't imagine it being easier to find than bleach, but it's worth a look.