Green water continuously return very frequently

moogie21

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My tank water continously become green almost daily with recurring brown algae. I change water frequently but it continues to re-occur.

I read it's related to sunlight and nutrients. First, my tank gets around 6-8hrs light a day. i've reduced this but doesn't seem to help. 2nd part is nutrient. not sure how to identify the nutrients causing this and how to resolve it.

I've tried using UV light and it helps a bit but this method can get messy. i'm hoping to avoid this method altogether.

Will purchase polishing filter pad in hoping will reduce this as well. we'll see.

any suggestion is welcome and appreciated.
 
In the past I’ve had luck ridding my tank of green water using the beneficial bacteria one would buy when cycling a new tank.
 
What's in the tank. Substrate, plants, wood..? Livestock?
this is an established bare bottom tank with no substrate, 40 gal, 2 goldfish, no plants/woods, 1 filter, 1 air stone.

I'm feeding them flakes, sinking pellets, brine shrimps.
 
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this is an established bare bottom tank with no substrate, 40 gal, 2 goldfish, no plants/woods, 1 filter, 1 air stone.

I'm feeding them flakes, sinking pellets, brine shrimps.

Several problems here. First, bare bottom tanks arenothealthy for fish. The substrateis the bacteria bed of an aquarium, more important than the filter when it comes to all types of bacteria. You need this.

Nutrients come from feeding the fish. Goldfish are known to be ravenous eaters, so you may be feeding them too much. The fact there are no live plants means there is nothing to use these nutrients--no bacteria and no plants--so naturally algae will take advantage.

Green water is one thing, due to unicellular algae. A UV can help with this, but it will not help with any other algae in the tank on surfaces. And once you get things under control the UV will be useless basically.

You need to establish a substrate, probably feed less, and reduce light.
 
Goldfish were the inhabitants at the time of my green water issue also. I added the beneficial bacteria before I went to bed and it was completely gone and clear in the morning. It never happened again either because I did try to feed less. Goldfish are piggies and very messy though.
 
Goldfish were the inhabitants at the time of my green water issue also. I added the beneficial bacteria before I went to bed and it was completely gone and clear in the morning. It never happened again either because I did try to feed less. Goldfish are piggies and very messy though.
what specific BB did you add?
 
My instance of goldfish and water so green you could not see the fish was over 15 years ago, so I would not bet my life on it, I believe the product I likely used was called Cycle.
 
It is more likely a coincidence that any of the so-called bacterial supplements would solve green water. Green water is caused by algae, not bacteria or ammonia.
 
Believe what you want, it may or may not make sense, this was my actual true to life experience. It worked completely and totally. Added it before I went to bed. Water 100% normal and clear the next morning. I was amazed also, figuring it was going to be much more of a problem to get the aquarium back in good shape. It was easy, stress free, and sucessful.
 
Several problems here. First, bare bottom tanks arenothealthy for fish. The substrateis the bacteria bed of an aquarium, more important than the filter when it comes to all types of bacteria. You need this.

Nutrients come from feeding the fish. Goldfish are known to be ravenous eaters, so you may be feeding them too much. The fact there are no live plants means there is nothing to use these nutrients--no bacteria and no plants--so naturally algae will take advantage.

Green water is one thing, due to unicellular algae. A UV can help with this, but it will not help with any other algae in the tank on surfaces. And once you get things under control the UV will be useless basically.

You need to establish a substrate, probably feed less, and reduce light.
i had substrate (rocks) previously in the tank and it was causing algae so i don't think adding the substrate will help for me.

UV does help but not sure if i want to continue as it can get messy.
 
Byron is right and covered it pretty well. You have a bare tank with no live plants. It has goldfish that are being fed and a light unit above the aquarium. If you have no live plants, then the light and nutrients will encourage algae to grow. That's all there is to it. Light, water and nutrients (with no live plants present) will equal algae.

To control green water algae problems, reduce light and nutrients, or add live aquatic plants to use the light and nutrients.

All fish tanks should have a substrate to stop the fish seeing their reflection on the bottom and becoming disorientated, as well as the other reasons mentioned above.
 
i've never plant before. what plant(s) do you recommend for beginners? something hardy, easy to maintain, and compatible with goldfish.
 
In my goldfish tank I had plants they could eat, anacharis and duckweed. I also had some amazon sword and java fern which they did not eat. I had some trailing houseplant (philodendron) coming out of the top to help with excess nitrates too. I found an old picture to show you an example. Like many aquariums, the look changed often and I was always adding more aquatic “salad” for them to enjoy. I also gave them frozen peas which I had thawed and removed the outer skin from. I’d toss in the little pea halves and the fish loved them.
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