What It Means To Be Overstocked?

[jiffy]

I have a 10 gallon aquarium that I have been keeping for a year and a half now. It's home to 6 cardinal tetras, 2 skunk cories, and 4 zebra dainos. I would really like to add 1 more small fish, possibly a dwarf gourami, but I know my tank is pretty heavily stocked as is.

My question is though, why can't I add another fish? Is it that there will be a lack of oxygen due to the surface area size? Is the surface area of the tank not able to contain enough bacteria to process the extra waste? Would adding an airstone or some live plants help aleviate any of this? What if I added a small sponge filter to give room for additional bacteria to grow?

Thanks in advance.

 

[akudewan]

I think all of the reasons you mentioned are right. Adding an airstone will definitely help, Can't say much about plants, but hardy plants like Java fern and some fast growing plants may help, provided you have required lighting and nutrients

 

[cane76]

if you think your tank is heavily stocked why would you wanna add more fish?
i dont think overstocking is down to air and bacteria alone.just because fish are alive dont mean they are happy and comfortable imo

 

[Tokis-Phoenix]

Your tank is not really heavily overstocked in the way of bioload, but more in the way of space- danios are very active fish and thus need alot of space to swim about in, you should really upgrade to a 20gal and then add another 2 danios and your stocking would be great then plus leave you some room for a couple more small fish, as it stands though i would avoid adding anymore fish as you are unlikely to enjoy your fish to their fullest no matter what you put in there as it is.

 

[jiffy]

cane - Its not that "I" think its heavily stocked, its that people have told me that and I didn't really understand why. While I'm no fish expert, my fish don't seem unhappy.

Tokis - thank you for the clarification, this is exactly what I was looking for. Are my 4 dainos actually unfit for the 10g? I would hate to get rid of them because I love their personalities, but on the other hand, I don't want them to be miserable in my tank either...