Algae in tank

Hi guys, experiencing algae in 1000L tanks and 25L barrels, they are the clear plastic type. first time algae has cropped up as i started with everything new in December… obviously I’m gonna need to drain tank and pressure wash it out, but any advice to prevent this in future or do you guys clean it all out every 6 months…:confused:

I am unsure what you use the tanks for.

BUT power washing will only remove the algae at the surface. Unless you kill it (chlorine) they will grow back even faster.

Can you reveal a bit more about the use of these tanks?

Using black barrels will cure this. Some people have reported shrimps in their wfp barrels - I suppose if you left them a few years you’d get Koi carp (only kidding). I’m told that Miltons sterilising fluid does the trick without effecting tds.

Milton is a bleach you can almost drink its used in the brewery trade and for babies bottles. It will kill the green algae after a soak. But it will affect your tds to some extent unless you rinse it properly.

hi thanks for the reply, i use the tanks for wfp window cleaning…

hi, i see the miltons via the link here, but if i was to get this, would 500ml be enough, n how would i best apply it, i mean bear in mind i cant get in the tank to rub it in can i, so short of mixing to a ratio and filling the tank up then draining it how do u suggest i use this? i have since blasted the tank with pressure washer, and have removed all visible traces, but am concerned now that it has been suggested that it will grow back even worse… fortunatly the water has not affected my jobs as yet but i am concerned if not sorted soon i will have major problems, such as green windows throughout my round lol… keeps up the suggestions guys, thanks Dave

Funnilly enough a lot of window cleaners in the UK are reporting algae build-up underneath the sills after they’ve cleaned the windows.
Add a small drop to a glass of water & test with your handheld - you will find the tds only raises marginally. So adding a small amount at a time into the tank will keep the algae at bay. Best to cover your tank with black plastic sheeting & have as liitle air as possible as algae needs light & air to grow. Depending on how big your tank is I would add 100ml to 250 litres but test first as mentioned. If you can empty your tank & try to rub in with an angled paintbrush or similar this should treat your tank. If you pressure washed - I hope you rinsed down with pure water after!!

Thanks for that Karlosdaze. thats a big help… ill get the miltons ordered… n cover tank… hope fully that does trick, looks like ill have to replace blue tubing from ro to tank as looks like algae has gone up there too. god help me, its like an alien invasion…

Better algae than sheep:

Wat the hell???

:smiley: but at the same time :(:frowning:

just use 10ml of chlorine per 100 Gal. of water and you won’t have to dump the water or pressure wash your tank. Then run it through an old almost spent DI that will remove the chlorine, if you don’t have DI you can use carbon all you need is a pool kit to test the chlorine. also use a small amount in your RO (one cap full) with out using your carbon filter this will clean out your RO with out any damage.

Good thinking Bill… you could run it through a final carbon block instead of DI to use the water in the system. And then do what you suggested above?

Mind you, I’ve been known to chemically treat a few pools - Chlorine doesn’t get rid of the algae unless its a super heavy dose. There is an anti-algae or algacide, but I’ve never tried it in a wfp system.

there is some stronger stuff its called MinCare it is 25% hydrogen peroxide but you need to be careful I have been burned in the past and you can’t remove it with out flushing the tank real well.


That’s great thanks guys for all your input, i have done the milton’s trick, only time will tell if the green stuff comes back, it was a stressful moment, thought i was going to lose my round over it.

i put 10mil miltons to 250l pure water, tds went up 198 from 0, tested it on my windows and its fine, amazingly - no problems, dries clear and still cleans good. can smell the bleach though. Have done a weeks work with it, pray tell no callbacks eh… but im optimistic, have covered tank for future prevention…

I can’t believe that raise in tds! Is that from the pressure washing or from Miltons? Usually, no way would you get away with that tds.

has to be from miltons, cause i got tds back to 001 after pressure water then wfp rinse.

mad the way the figures go eh., but yet another day passed, no complaints, even had a call thanking me for the “marvellous job”

Miltons will send your tds up by 10 parts so if you have a meter that reads to 10 it will raise it over the 10 if it reads to 100 it will send it over the 100 and the tds screen will go blank !! even if its mildly diluted.
Simple answer is to keep your water in light proof containers as the army does.