Severum in a 75 gallon, which of these options would you choose?

[neutrino]

I started keeping fish in the 1960s, have bred many and, as one of my favorite fish, I've had Heros (severums) for most of the past 27 years, plenty of times in a 75 gal tank. It can certainly be done. As mentioned above, I wouldn't keep adults of one of the large species in a 75 and as mentioned above Heros and most types of geos typically get along well. They're frequently found together in nature and generally occupy different niches in a tank. I bred rotkeils and Geo tapajos red heads, both, sometimes in the same tank. Because of this, and sometimes having parents, fry, and juvies of each all over the place I've had them in various size tanks.

Tank size and stocking is always a debate with varied opinions. Part of making a smaller tank like a 75 work is keeping compatible species and how you scape it. I had a wild rotkeil, 2 wild Peru scalare, and various numbers of red head geos in a 75 for a while, including a breeding pair of the red heads, and it made a nice tank without any issues, including when the geos had fry. Also had a group of 6 adult rotkeils and a group of red head geos in a 6' ft tank and that was a nice tank. You can always get the rogue sev or geo that might get overly rowdy, but sevs and geos, sometimes with wild scalare, have always worked for me.

 

[KidMoe]

A lot of support for the single Severum with Geos option, which I'm happy to hear since that sounds like a great combo. So my tentative plan is to have a single Severum with an unspecified number of Geos Tapajos. I plan on getting all the fish at a very small size and grow them up together. Maybe start out with about 7 of the Tapajos while they're small and remove males, as they grow, until only one remains. I'll wait and reassess how many females to keep based on tank dynamics and space. Should I start with 2 Severum in case 1 of them is a jerk or just start with 1 and hope for the best? Also, I assume a small school of dither tetras would still be appropriate with this stocking or no? My last decision will be the look of the tank. I'm envisioning either a dark background/substrate look with a Gold Severum for a pop of color contrast or going a little more natural with a lighter substrate and a Red Shoulder Severum instead. Either way, sand on the bottom and typical drift wood and rocks scape.

 

[ryansmith83]

Only start with one Heros. You’ll quickly have a dominant fish emerge and hound the other, in most cases. Heros can be especially snippy with each other as juvies.

 

[neutrino]

So my tentative plan is to have a single Severum with an unspecified number of Geos Tapajos. I plan on getting all the fish at a very small size and grow them up together. Maybe start out with about 7 of the Tapajos while they're small and remove males, as they grow, until only one remains. I'll wait and reassess how many females to keep based on tank dynamics and space. Should I start with 2 Severum in case 1 of them is a jerk or just start with 1 and hope for the best?

There's no particular advantage to removing males from a geo group and keeping extra females with a single male-- except the harem breeding species in the Steindachneri group. As I mentioned earlier, an odd female or females will sometimes be a nuisance to the pair, trying to cozy up to the paired up male. With geos I'd either keep a pair or keep the group.

Severum wise, a single Heros in a tank generally does just fine in a compatible community, but many don't realize Heros are social fish and, except when spawning, are found in groups in the wild-- see videos below. A Heros group makes a nice display and lets you see some of their social behavior. Even among social cichlids, keeping just two doesn't always work. Juvie Heros being snippy-- for me not so much; depends a bit on species, age, size of the group, etc. Heros don't like feeling crowded in my experience, but tanks and fish behavior are a matter of scale, a 75 gal that might crowd two adults has worked just fine for me with groups of juvies.

Up to you, but if it was me I'd either pick out a nice one you want to keep or get a group of small ones to grow out for a while, then keep one you like.