Let's Do A What If ...?

[This Old Spouse]

All my tanks were started when I was a complete noob. They have progressed fairly nicely, but I still have issues with all to some level. 
 
What if I was to go out and get myself a brand new tank and start all over? I'm actually looking at a 40g breeder tank so I can concentrate on cory as the main stock. 
 
Live plants, of course, with rocks and driftwood for accents and to make caves.
 
Sand substrate. Play sand, in my case, because I think it gives the tank the natural appearance that I'm after.
 
Expert opinions:
 
How deep should the sand be? And what does a person do to avoid the layer of dark matter that forms under it? 
 
Do I need a CO2 system to have plants grow well? It's weird, but the 20g I have has no CO2 but I have very little algae (only on the glass since my otos went belly up) and I think I can thank the RCS for that. I'm a bit terrified of CO2 systems because I'm afraid of gassing my fish, the expense, and what to do when I leave town for a few days.
 
Setting up filters and powerheads to be most effective.
 
I'm sure all these questions have been answered during my tenure here, but I think if maybe I see it all in one shot I might be more apt to get it right. I'm thinking about starting the tiger barb tank all over again too. It and the 55g are still rife with BBA, and I'm afraid the only way to get rid of it is with CO2. 

 

[silenthawk2x3]

I don't do CO2 personally because I feel that the expense is too much/time/hassle/fear of killing every living thing in my tank. Instead of all of that I do dirt! If anything I would say do a dirted tank with your play sand. My cories love it and I have a hearty shoal of twelve in my 55 gal that is dirted. The plants grow wonderfully and the dirt doesn't bother the fish as long as it is organic (no ferts/pests). My advice would be to do an inch of dirt with an inch of play sand on top. I've had the same set up, perhaps thicker, in my 55 gal and have only had one problem. Too much plant growth! I haven't had a problem with algae or diatoms in the sand either. I used pool filter sand because of the availability of it, but I'm sure play sand isn't too different.

 

[This Old Spouse]

Good idea. I had thought about dirt but then kind of forgot about it. I like the thought of that over CO2. I wouldn't have to worry about dosing while I'm out of town either. 

 

[silenthawk2x3]

The dosing is a huge part of it. I'm still a college gal so I'm not home to watch my fish as often as I wish I could be. I know that I've set up a stable enough ecosystem for my fish to not only survive, but thrive and for the plants to be healthy too. I do minimal maintenance on the tank, besides the occasional water change and testing, but besides that it is a very stable tank. No fish have died, nobody is eating anybody else, nobody is eating my plants. It has been the most hassle free tank I have ever had. I actually left it for a little over a week recently and came home to find that, if anything, everyone was happier than when I left them. All of my angels and tetras were colored beautifully and looked well fed. The corydora horde was roving around happy as ever and the BN plecos were munching away on everything. Even though the light had been on 24/7 I didn't have any algae, even less than I perhaps had when I left, but while I can't say that the fish didn't help out with that, I know its also due to the fact that everything is so balanced. Emulate nature is the way I roll (environmental biology major) so that's what I do for my fish.