Green algae bloom

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Aquarium Advice Newbie
May 2, 2021
I have a green algae bloom in my tank it’s not that new I set it up at the end of December. I recently just changed the filter and realized the water was really cloudy. It has now turned green. I’m not sure what to do. I read something about a UV filter or something? Any tips


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A UV filter should clear up your green water, but it wont solve the root cause.

Green water is usually caused by too much light or high levels of nitrate and/or phosphate which in turn is down to overstocking, overfeeding and/or insuffucient tank maintenance.
I do regular water changes about 25% weekly, I checked the water and its 0 for nitrite and nitrate .Could it have something to do with me messing around with the filter and removing the foam. I didn’t realize that that’s one of the worst things to do. I’m not sure if my tank was fully cycled yet. There also isn’t that many fish in there. It’s a 30 gallon and there’s 4 honey gourami 2 adult guppy’s 6 baby guppys and 6 rummy nose tetras. Will the green algae go away on its own. Would adding pothos help in any way??
Hi Leanne3, I had exactly this problem several years ago. I tried everything but failed, until installing an inline UV light hidden inside a cupboard below the aquarium. After 4 days the tank changed from green to white bloom! But when I added a flocculent, and returned 30 minutes later, the tank was crystal clear! I guarantee this will work for you. I tried covering tank for days, adding daphnia inside a meshed container to protect from fish, tried adding a flocculent on its own. None worked. I have never had this problem again, but if I ever do, my UV will be turned back on! Good luck.
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