How do I figure out the dimensions of a bow front tank?
You can give the shortest and deepest width or you can give the average, either is good enough!
I just measured the flat sides. Its 3 feet long, 1 foot wide, and almost 2 feet deep...
The loaches and rosy barbs are very likely to be stunted in an aquarium this size and the gourami is moderately likely to become stunted; 3 ft is just not enough space for a 5" active loach to swim around in and for a 5.5" barb (I suspect that the barbs usually do not reach their full adult size *because* they they do not get the space that they need). Personally, I would not consider
Botia kubotai, nor
Puntius conchonius, for any aquarium under 5 ft in length and opeline gourami for an aquarium under 4 ft in length. So if this was my aquarium, I would be thinking about an upgrade or trading the fish in for something more suitable. I know that a lot of people do keep these fish in aquaria that are as small, but I really cannot honestly say that it is any good for the fish, and my priority as someone who is doing their best to be a responsible fishkeeper is to do what is best for the fish, which is usually trying to imitate their natural environment to the best of my ability.
[…] He swims away from all the other tiger barbs and seems to school more with my rosy barbs for some reason. […] OldMan47 told me in a different post that he would keep the peaceful tiger barb by himself since he was just fine for the first 4 years by himself. […]
I work on stock based on what is most natural (which is usually the ideal) for the fish, so for shoaling species, I will always recommend that they are kept in appropriately sized shoals. Obviously, the tiger barb you already have is used to being alone, and might even think that it is a rosy barb, but I would still expect it to do better when in a *large* group of its own kind. At the end of the day, this sort of decision is always down to the keeper of the fish in question and I do not consider it as important to make a specific choice in this situation compared to when stocking form scratch.
Because I see adding a new species as "stocking from scratch", I advise you against more species as it is unlikely that you will be able to have a reasonable sized school (10-15+) of a new species, and it is unlikely that an territorial species will fit in with the loaches on the ground and the gourami above while I can't think of anything mid-water.
I think my tank is too small for all the fish you are suggesting. Kinda making me doubt its a 55 gallon??
It is very likely a 55 US gallon because of the height, but unfortunately, the height does not help with the stocking. There are some fish (like angels and discus) which must have a minimum height tank (2 ft), but most fish can live in any tank starting from one that is 12" tall (and some fish can even have a shorter tank without any problems). What this means is that if your in terms of maximum fish size, there is no difference in stocking restrictions between a 3*1*2 ft and a 3*1*1 ft tanks. In terms of numbers, there is a little bit of difference, but not really all that much, maybe only 10% or so. What the extra 1 ft in height gives you is more stability in water parameters, which is especially useful if you have soft water.
To roughly estimate how much water your tank holds (using estimates based on the numbers you gave):
-take the shortest front to back distance (30 cm), and multiply it by the height of the water form the top of the gravel to the surface (50 cm), by the length of the tank (90 cm), then divide by 1000 and you will get the volume of the main part of the tank in litres (135 litres,
i.e. 35.5 US gallons)
-take the difference between the narrowest and the widest part of the bow front (estimate around 15 cm) and do the same as above (15*50*90/1000 = 67.5 litres), then divide it by two (67.5/2 = 34 litres, i.e. 9 US gallons)
-finally, add the two volumes together (135+34 = 169 litres,
i.e. 44.5 US gallons) and you get the total volume
So if you take the above volume and calculate it for a substrate-free tank, filled to the rim (44.5/50*60), you will find that you will get 54 US gallons as the "total" volume, which is what manufacturers often use for selling the tanks and it matches what you thought.
Note that if you have any large rocks or bogwood for decor (and you should have at least some bogwood for the pleco), then that will impact how much water the tank holds. This calculation is actually very important because when treating fish, you need to use the *actual*, real amount of water in the tank to calculate dosing, not the theoretical, manufacturer's volume. It is especially important if treating with medications that it is easy to overdose on (for example, whitespot treatment on loach tanks), as most fish medications are quite nasty to the fish as well, especially to scale-less fish like loaches.
When I had a couple of tanks that were similar to yours (55 gallon AquaStyle 980, which were 98L * 47W * 60T cm bow fronts), I had for soft and neutral water:
* 20 (up to 2" adult size) tetras or harlequin rasboras of one species
* 1m 3f bristlenose plecos (5 caves, bogwood)
* 1m 2-3f harem South American dwarf cichlids or 2m 2f pair SA dwarfs
* 10 (up to 2" adult size) Corys of one species
And for hard water, I had:
* dwarf Malawi cichlids
* 3 unsexed small plecos
I know that I'm a bit vague about the exact stock, but that is because I had the tanks for around 5 years and swapped the stock with other tanks for breeding,
etc, so have had quite a selection of fish in these tanks. The other main thing to consider is that you should avoid active fish, such as zebra danios, but can go for larger-than-expected slow fish, like plecos.