Capacity of 125 gallon tank w/ 20 gal. sump?

[Cortes427]

Hello, I'm wondering what you guys think about the fish load in my 120 gallon FOWLR tank with 20 gallon sump... I have three small green spotted puffers, a Niger Trigger, a Humu Humu Trigger, a Sailfin Tang and a Powder Blue Tang. In your opinion, is my tank below fish capacity, just right, or above? Thanks for your opinion in advance!

Freddy

 

[austinsdad]

How long have they been in the tank and what are your average nitrate readings? Are the fish small and still reaching their respective full sizes? Don't those puffers grow substantially? If so, my gut tells me you're over.

I am interested in your nitrate readings though.

 

[Cortes427]

The three GSPs, two triggers, and sailfin have been in the tank approximately three months, the powder blue was a recent addition as well as being the largest of them all at roughly five inches. The GSPs are still under three inches and have a potential size of six inches according to my research. The Sailfin and both triggers are appoximately the same size which may be between three and four inches. My nitrates are on average between 10 ppm and 20 ppm and have been decreasing with the addition of a deep sand bed, chaetomorpa, and caulerpa in the sump.

 

[pat8you]

I would say you shouldn't add anything else for quite a while. If you have a deep sand bed that is helping to reduce your nitrate levels that is good but i would be more worried about space and aggression in your tank. There is no set rule to how many fish you can have but in your case with that many aggressive fish that are all going to get bigger ( which also usually means more pushy) i would say you should stop. Also that is a lot of fish to add in that short of a time span. I would give it a 6 month minimum to understand the dynamic that is going to develop between your fish before you start adding more.

 

[Cortes427]

@Pat, thank you for your input. The recent addition of the Powder Blue Tang was an impulse buy, it was such a beautiful fish to pass up and I ended up justifying it by arguing to myself that I needed another tang to complement the two triggers (weak argument I know.) As far as I'm concerned the Powder blue will be the final addition to this tank. I was concerned more with the Picasso triggers aggression towards the powder blue but he has left him alone. I imagine that because the Poweder Blue has a good inch in size more on the Picasso it's not an issue. The Sailfin, however, showed the most aggression towards the Powder Blue when I introduced him into the tank. He seems to be integrating nicely for the time being and I hope it stays that way.

 

[pat8you]

Yeah i really like the powder blues as well. I can't fault you for picking up one of those. I think you have a resonable amount of fish in there right now. I would just give it a little time to make sure everyone continues to play nice and that your tank can handel the load. You should get a picture of all the fish for us.

 

[Cortes427]

Here is a short 30 second video I just posted on youtube YouTube - Aggressive saltwater aquarium

 

[pat8you]

Some very nice looking fish. Thanks for the video.