I try using the Algaway 5.4 but not effective. So far, I have dose for 3 week of microlift bacteria into the filter chamber, the algae is getting lesser each day.

I think the bacteria also consume the same type of nutrients as the algae. So less nutrients for the algae mean less chance of them growing rapidly. IMHO.

Bro noidea, thks for the info... I will go and get Algaway 5.4 or Microlift Bacteria if the algae condition worsen further... :o

I am thinking if the algae bloom is due to the higher flow rate as I change the 2 pumps recently? Could it due to this? Furthermore I remove the mesh cover at the overflow to prevent the detached black hair algae from clogging it. With it removed, the water being 'suck' in is amazing... normally after a heavy feeding, the water surface will have a layer of foam/bubbles and it will take a while to be gone. But now the foam/bubbles is removed in a short duration. I kind of love it :D here is a video showing how it works...
http://i1371.photobucket.com/albums/...ps7qiszzbk.mp4

Cheers!

nice solid over flow. this way your water surface sure to be always clean :)

I don't think water flow rate will cause the algae bloom. I have 4 pump in my pond, I still think the flow rate is not enough. The higher the turnover rate, the better the water will be. IMHO.

Foam/bubbles is sign of the water have too much protein/etc and the bacteria in the filter are not at the optimum level to clean them up. (layman term)

When my pond display too much foam/bubbles, I will add some bacteria into the filter and somehow the next day there will be less foam/bubbles.:)

Re: Foam bubbles

It is possible to build a foam fractionator to deal with the Dissolved Organic Compounds which cause the foam.

It need not be a permanent fixture, but is rather large.

http://www.koiphen.com/forums/showth...-1300-1500-gph

You will be able to get by with 4" pipe for your pond. Getting rid of the DOCs will improve water quality greatly. The only other means of removing DOCs is water changes.

Algae bloom generally points to

1. too much nutrients in water
2. BB die off in bio filter causing #1

I think that the installation of beefier pumps may have stirred up collected dirt that settled out in the past, causing a nutrient spike. I suppose that this will resolve itself after a new equilibrium is achieved.

This one a bit 'chim' for me...

Yes bro... always like yr advise :) I believe point 2 is the cause! I did stir up quite a lot of dirt from the filter chambers and I believe quite a lot of the BB were destroyed in the process... really appreciate it.

I have some BB stuff that a very nice bro passed to me some time ago. Wonder if there is expiry date for this? Maybe I just dose some inside to try :)

Bro, in normal situation there is no foam/bubbles, these foam/bubbles only show up immediately after a heavy feeding... do u experience the same after a feeding or yours will have the foam/bubbles as and when regardless got feeding or not? Care to share a pic of your pond :)

My pond normally don't have foam as I have a clarity tower unless the koi start to spawn then there will be a lot of foam. The water is fast flow toward the surface skimmer.

I have to go find the old photo of my pond.