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Fish/jack dempsey care


  I have had a jack Dempsey for a couple of months now. he has grown from about an inch to maybe 3.5 inches. For about a month now I have had rapid algae growth it is brown and grows on the glass I have been cleaning it off and changing water but it isn't working. I took my entire tank apart changed all the water, and put him in about a day later. The algae came back again. I don't think it is bad tor the fish, but it I'd getting very annoying to clean

ANSWER: Hello Eli, I have a quick question that I need to shoot back at you in regards to your algae growth. There are a few main causes for brown algae to grow. The reason I think you are having the problem is due to a lighting issue. What kind of lighting are you using for the tank? Also what size tank is it? A few ways to clean this up would be a possible additional light or something with a higher wattage, or adding a fish like a plecostomus to the tank. I would think that it is a lighting issue though. So if you could just message me back with what lighting type you have and I will get back to you further.

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QUESTION: Well, it is a 30 gallon tank, It is an aquarium light that rests on top it says it registers 120 volts and 20 watts. It lights the tank sufficiently. Also my fish is very aggressive I have tried two plecos but he just kills them. I would like to try any of your ideas.

Alrighty, Your lights seem to be fine. Never mind about the lighting that should be fine. The brown algae can be from too much lighting as well. Anyways the problem might also be your water flow. If the water is not flowing enough for your tank a powerhead will solve your problem. As for right now, do a 30 percent water change and make sure you wipe down all of the brown algae from the rock, and sides of the tank. Take note on how much comes back over the next few days. If it is less, more or the same amount. If it is the same or more, the problem is one of three things. Either your water is too hard, the lighting is too much, or the water flow is not efficient enough. Your filter can be working perfectly but sometimes tanks need some additional water flow. Also, if your tank is getting direct sunlight, that can cause algae growth. Observe your water flow and if you think it is too still you could purchase a powerhead and see if that helps the problem. Whenever you take those notes, shoot them back to me and I will gladly continue helping you troubleshoot.


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Jordan Gobely


I can answer most questions about fish care and maintenance. I am not an expert on saltwater aquariums but I am researching more about them on a daily basis. I have kept many different tropical freshwater fish as well as cichlids. Brackish water is my weakest category but if you have a question feel free to ask and I will do research on it myself.


I have kept fish for over 10 years. I am also an employee at a pet store and the head of the fish department. I am going to school at Emporia State University and studying biology with a concentration in ecology and biodiversity for undergraduate work. Right now my job is to care for and maintain the fish department at a local pet store. As far as water quality, I am well versed in different practices you can do to help improve conditions and what levels to look out for when testing the water.

I am majoring in Biology at Emporia State University and have researched fish reproductive behavior for the past decade.

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