Stocking List Sanity Check

Well, IMO you're 'Off Base'. And, it seems like you have fallen for the 'I want to try everything - at once! - condition. That is something that is actually rewarded sometimes in the Mbuna, African Cichlid world. Not so much in New World cichlid keeping.
And so, the 300 gallon tank is (probably) big enough to realize your proposed stocking plan. Yes. But once realized, it would look a bit like, well... everything. Too many species! I believe you need more of one or two species, less of others and none of some others.
So, let's work through this thing first with some of your own priorities. That will help a lot to inform stocking decisions with your Cichlids. If the tank is not necessarily, 'all Cichlid'?
- Do you want any non-cichlid 'dither fish' in there? A pretty good-sized school of Big Tetras? Silver Dollars. (Giant Danios?!!)
- Do you have a 'thing' for catfish? Is a larger-sized, armored Pleco something this tank definitely has to have? Or, are you more into a school of Pictus Catfish? Decisions in this direction will inform an overall aggression level for the aquarium (milder).
- How intent are you in spawning/breeding behaviors? Some pretty small New World species can be legitimate 'tank wreckers' (Neetroplus nematopus anyone?) when spawning. Even in some very large aquariums! If you are really not all that interested in spawning behavior? That informs stocking decisions, as well....
- How interested are you in keeping some pretty rare species? F1's or possibly wild caught stuff? Having cichlids like that will establish stocking priorities inside an aquarium - fast! ($$$).
-
So, c'mon back with some answers to those Q's. We'll come back with some better-informed stocking recommendations for you.

Auballagh, thanks for the reply... so to my thinking, the Severums, Acaras, and the Altifrons are "must haves" (numbers can be played with). The Tiger Oscar is a "would like to have". If he doesn't go in the 300g, I'll set up another 75g and keep one alone in there. Everything else can be modified or deleted. I've looked at the possibility of adding something like a Raphael Cat, a Rhino Pleco or a Spotted Hoplo Cat (I'm trying to stay on the milder side of the aggression spectrum). As far as dither fish, I'm not opposed to it, but if it came to deciding between dither fish school or an additional Cichlid... I would choose the Cichlids (I have a plethora of other tetras in my other tanks. Everything from tiny little Embers through some good sized Congos. Nothing as large as a Silver Dollar though.) While I'm not looking to drop $400-$500 per fish for rare wild-caught or F1's, anything less than $150(ish) for a fish is totally do-able. I'm not conversant enough with the New World Cichlids to have my heart set on any super unique/rare fish. I enjoy the **** out of my Rams and my Keyholes which is why I'm wanting more and larger Cichlids!

Alrighty then.... given your stated priorities, here's some choices you could consider that I believe should work pretty good.
- Option 1 -
- 8 each, G. altifrons. Ideally, you want at least 5 - 6 females in this group. This Earth Eater species is actually pretty mild. But, when larger/adult sizes are attained... be ready if necessary to pull out a fish, esp. a weaker male if it gets bullied and beaten down by the dominant male.
- 7 each, Heros sp rotkeil. Here's your 'oh wow' fish. And, I don't believe these will disappoint. Dig deep though ($$$), at $35 to $65 bucks apiece, well..... you gotta pay to play with these boyz.
- 1 pair, Electric Blue Acara (EBA).
-
- Option 2 -
- Substitute the EBA pair for a single Chocolate Cichlid, (Hypselecara temporalis). This good looking, peaceful giant ('budfy?') will be your 'centerpiece' fish. I love these things, and don't know why they aren't as popular as they used to be in the hobby....
-
- Option 3 -
- Substitute the EBA pair for 5 each, Flag Cichlids (Mesonauta festivus).
-
Maybe you can tell... I'm not much a fan of the Electric Blue Acara. I can't deny though that these hybridy things do have their appeal though, and are quite popular. But for me personally, I'll just stick with plain ol' Andinocara pulcher.
- The Festivum option is intriguing, because it will be pretty interesting to see how these normally quite shy, retiring Cichlids do in such a busy community tank. Hopefully, that group will 'bold up' a bit, and come out and play with all of the Red Shouldered Severum in there!
- Water Quality: Your water parameters will work well for keeping the G. altifrons. If your local water gets much higher in PH though, it could start causing stress for this sensitive species. And, be ready to start pushing water in some higher frequency, high percentage water changes. If your Nitrates get up near 20 PPM in the aquarium, you could be in for all kinds of trouble with those Earth Eaters. (In fact, would it be possible to rig up a water addition/overflow system for this aquarium that could push anywhere from 25 to 50 gallons a DAY through it?).
-
- What are the dimensions of this aquarium?
- Are you going with a high-mount plant refugium? It works pretty nice to set up something with a side overflow, with water pumped up to it directly from the tank. Depending on the length of your aquarium, you could have a decent 'trough' made up in acrylic at 72"L X 14"W X 12"H. Floaters with high-quality LEDs should get the trick done pretty nicely, and will help a lot to hoover up those toxic Nitrates and Phosphates out of your water.
- Definitely recommend going fluidized media with your sump. A straightforward and simple build with dual, linear air stones will work best, and these are pretty easy to go DIY. Go with K1 micro-media. And, the results are definitely worth the patience and extra time it will take to build up your beneficial bacteria colony on the fluidized media with fish less cycling.

https://www.cichlid-forum.com/articles/ ... _cycle.php

Looking forward to seeing what you get, and definitely keep us in the loop on your build process. Send pics!

Not too surprised 'Oscar6' jumped in with the centerpiece fish recommendation for an Oscar in this tank. He does love him some Oscars.
And, totally concur with his recommendation not to keep one alone in the 75 gallon tank. That arrangement never really ends well, unfortunately.
-
As for your (custom-made?) acrylic tank, I REALLY like the 36" width you plan. The 30" inch height looks good. Any higher than that though, and it gets pretty tough to do any work inside the tank.
I really DO, strongly recommend squeezing out as much length as you possibly can for this aquarium. The 72" inch length is good, yes. But, just a little longer (even at 80" inches) would be much better. The largest, bottom footprint you can fit for this build, will work best for keeping those fish, esp. with that stocking arrangement I recommended to you. Those G. altifrons as a larger-growing Earth Eater species, are gonna be very busy and move all over the bottom of that aquarium. Give 'em plenty of room! :thumb: