Community vs Species tanks

[seangee]

Recently I reduced my tanks from 4 to 2 with the two I shut down being a 20G and a 20G long. Part of the reason was space and a small part was the maintenance effort as I was injured for the better part of a year. But the 20 long had to go because it was on my desk and I replaced that.
Most of the tanks I have kept over the years have been general community tanks or geographically themed communities. I did have intentions of biotopes a few times but stocking a true biotope (plants and fish) can be expensive and difficult, hence the regionally themed.
I have also long maintained that community tanks don't need centre pieces because the community can be a centre piece. Case in point - my 200l community has between 30-40 cardinal tetras. Nobody would even notice if I added a large pretty fish because the cardinals grab your attention.

Yeah yeah I'm rambling
So now I have a 29l QT with 13 nannostomus marginatus. And I am loving it as a tank in its own right. I know that this tank is theoretically too small but I am leaning towards keeping them there once the quarantine ends. ATM I am changing 50% of the water every other day, and I spend less time doing this than I do feeding the dog. These would be almost invisible in the community. Also I can set the parameters exactly to their requirements without having to find the best compromise that works for everyone in the tank. OK that may change if I add shrimp. I am considering that as these are fairly slow feeders and not keen on eating off the bottom - so inevitable there will be uneaten food, even if I feed sparingly.

What would you do after quarantine?

The big community stays but I am seriously considering adding a few small tanks which will allow me to keep different fish that wouldn't go with my community. For those that keep lots of smaller tanks what are the pros and cons?

 

[anewbie]

The largest con is only exist if you put fishes in the small tank that really need larger space to show their true form. Of course there are many species that will do well in smaller aquariums - there is a secondary negative that small aquariums are less tolerant of mistakes because there is less water to absorb the mistake - mistakes occur in all forms from temp change during water change to unintended addition in the new water.

On the bright side the smaller aquarium has less in it when you goof

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Having said this there is an obvious fix to this issue and that is to have 10 species aquarium that are 30-100 gallons each And (since i like dwarf cichild) those gallons are not taken up by excessive height in the aquairum. My dream aquarium is 14 feet long 5 feet wide and 14 inch high....

 

[seangee]

there is a secondary negative that small aquariums are less tolerant of mistakes because there is less water to absorb the mistake

Since they prefer negligible hardness ther is fortunately not too much to go wrong in this particualr tank as I use RO

And (since i like dwarf cichild) those gallons are not taken up by excessive height in the aquairum. My dream aquarium is 14 feet long 5 feet wide and 14 inch high....

Sounds good - since I favour the nanos I'd take that with only 14" wide and hundreds of fish

 

[GaryE]

I really like single species tanks, probably because I'm drawn to tiny fish. I don't usually use tanks smaller than 40L. I have some stored, and they are for fry or ailing fish. The North American standard 10, 15, and 20 gallon are good sizes for what I like.
Smaller tanks only hold pairs, and because I have large hands, I hate working with them.
Cons? You have to keep up with the water changes, and you have to know your fish. You can never buy a 3cm fish thinking it will stay that size if it gets to 12cm with age. Small tanks don't forgive.
Pros? You have space to indulge your curiosity, as you can end out several 10g/38L tanks in the space demanded by one big tank.
Many single species tanks allow for breeding, if they are set up right. Even if it's not hands on breeding, and you let the fish do what they want, the development of fry into adults and the long lives of single species communities are great to observe.

I'm into killies, and they are shy fish with specific demands I can meet in single species tanks. Tankmates often kill these timid eaters. The killie hobby is an old one, and was established when a 38ltr tank was big. Before silicone, tank sealants were messy, always had to be replaced and leaked. I remember my father mixing up tank repair concoctions at the kitchen table. Tanks had to be small and people often used 10ltr tanks for pairs. That, I don't accept. But if you are into breeding, 40L tanks allow me to have multiple pairs, fry tanks, etc.

You see different behaviour in single species tanks, no inter species aggression or fry predation, no weaker species being forced out of the natural zone by more robust ones, easier feeding of shy fish and often even better colour from small fish. You can keep oddballs with specific needs, like your pencils.

Larger single species tanks can work even better, depending on the species you want.

I stopped worrying about centrepiece fish 40 years ago. I realized that people who came to my house rarely paid any attention to even my best set up tanks, and that my tanks were fundamentally for me. I don't need some clunking fish to draw my eyes to the tank. I look even if the fish are shy and it takes me a second to spot them. All you need is fish worth spotting.

 

[anewbie]

I found over the years i've moved to wider aquariums esp with tetra and dwarf cichild; the standard with of 12 inches (29/20 long) is just too narrow. My bed room aquarium for example is 30 inches wide and 72 inches long and my office aquariums are 48 inches wide and 120 inches long on one side and 96 inches long on the other side. 1/2 my dwarf cichild aquariums are 16 inch wide and random length based on space but 48 inches when possible. Certainily larger dwarf cichild species really require that extra width and length. What i've concluded is that even in a larger aquarium i will never buy a 1 foot cichild again (i have chocolate and geo dicrozoster in the 600 and 500); and those monster really need larger aquariums. No clue how people keep oscars in tiny 200 aquariums.

 

[GaryE]

The Cichlid hobby almost runs in parallel to other aspects of the hobby. I am in both worlds. I don't have single species tanks for Cichlids, as I like to have a species or two up around the surface. The same is true with my Cory tanks.

When I talk about smaller (40ltr ish) single species tanks, I'm thinking of killies (lampeye and plant spawning), small tetras, barbs or rasbora types, etc. Micro-fish that may or may not shoal.

I don't like getting on the treadmill @seangee is on with the heavy, methodical water changing. At some point, you won't be home for a few days, you'll get sick, fall in love, change jobs - something will get in the way of every second day. It's good to have a slightly forgiving set up for when those things happen.

 

[Magnum Man]

when I had tanks 30 years ago, I mostly did species tanks albeit for fish like piranhas, and oscar's so now days I do almost all community tanks, and find them most challenging and rewarding, when they truly work... I've been adding shrimp as part of the community, for a few years now, though I started with amano shrimp... lately I have added 4 - 10 gallon tanks for breeding different colored "neo" shrimp... to continue with the community themes, I've been starting small live bearers to the shrimp breeding tanks...

so... I absolutely hate small tanks, 30 years ago, I had probably 25 - 10 gallon tanks... I told myself "no more"... they are just too much work, and too unstable... if I had my way, every tank would be at least the standard 55 gallon... so much easier to work on, and much less work, than a 10 gallon, and much more stable... unfortunately the house being a partnership, limits how many bigger tanks I can have....

with the addition of terrestrial plants to the 10 gallon tanks, they have been more stable, but are at 50% water changes, so the occupants need to be able to handle that, so just from the water changes, they are not as stable, with a lot of water related fluctuations

 

[seangee]

I don't like getting on the treadmill @seangee is on with the heavy, methodical water changing. At some point, you won't be home for a few days,

And that may be a good reason- especially if I were to get fish that don't require many plants (or destroy them).
For now I am doing it every other day, not sure if I have to. This particular one is likely not even cycled but I think I have enough plants for that not to be an issue. And as its in my office I don't even have to leave my chair to change the water
If I use the totally pointless measure of litres / fish my community tank is heavier stocked than this one, and even more so if I use the equally pointless inches per gallon.
I also change 20% of the Flex 15 every other day - it was fine when I went on my 2 week hols, as was the much heavier stocked community.
I guess the big test will be in September - when I have another 2 week holiday planned.