Growing Green Water Advice?

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Aquarium Advice FINatic
Nov 22, 2012
Hello I am trying to culture green water for daphnia and I have not had much success. I recently tried added organic fertilizer but I believe I added too much. The water was dark yellow and smelly. I did this in a 2.5 gallon fish bowl with a heater and air pump next to a sunny window with a cfl lamp shining on it. If anyone has had any luck with growing green water please help me out!
In my next attempt I am wondering if jars will work better than a bowl that way I have more cultures??
Also to use or not to use a heater and air pump??
And what to use for nutrients(miracle grow, less organic fertilizer, lettuce etc.)??
Lastly would DIY co2 help??
You can YouTube this topic and see a bunch of different setups. Did you have an air stone to keep the green water from settling at the bottom?
I just had an air pump with a tube no stone on it. I wanted to see if any other members culture green water.
I tried it and had mixed success. Any fertilizer will work and I would use 1 ml per gallon. The key is using a good strong culture to begin with and not getting water contaminated through the process. There is a site called florida aqua farms that can set you up with everything.
I can't just use fish tank water to create algae I have to use a starter culture?
Fish tank water is no good due to cross contamination. Make sure all of your containers and tubes are sterilized. Start with fresh saltwater of salinity around 2.018. Keep in mind that salinity will increase with evaporation.
This is what I have at the moment. A tablespoon of organic fertilizer a mini heater a air pump with a pvp pipe a lamp a 2.5 gallon bowl with aquarium/ pond water and a clump of algae from the pond as well. I don't really care what kind of algae grows I just wan it to be edible for daphnia and not poisonous. I recently saw larvae looking things in the water that were dead so I don't think anything can survive in the water although algae is starting to grow on the sides and the clump of algae is thriving. The water stinks though and is very nasty looking :/ .


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If you've ever had a dirted tank with say organic miracle grow dirt and a t5 light or 2, then you know how to grow green water lol
I can't really get unicellular free floating algae to grow :( I can get everything else though. The stuff I have sinks to the bottom :/
Buy an algae disc from Florida Aqua Farms. There are numerous how-to's about growing it on the internet. When I decide to culture rotifers I do it in two 10 gallon tanks half full and culture about 14 gallons of phytoplankton a long with it. I stock up about 10 gallons of phyto before I start my rotifer cultures so I always have a reserve. My process only last about a month, but it gives me enough rotifers to get my larval clown fish to the juvenile phase and on to baby brine shrimp. I sell off the excess phyto to my lfs afterwards
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