Benefits and questions about building custom tanks

[kwamjing]

With small tanks (30 inch front glass) I was able to make a shape that fit better than a commercial one in the time I watched a video and worked for half an hour.

Of course, smaller is easier. I just don't believe in small aquariums. I would never own, or recommend, anything smaller than a 40 gallon long for most species commonly found in an LFS. I fully realize the vast majority of people on this forum will disagree, so please, just don't bother.

 

[SammyTargo]

Of course, smaller is easier. I just don't believe in small aquariums. I would never own, or recommend, anything smaller than a 40 gallon long for most species commonly found in an LFS. I fully realize the vast majority of people on this forum will disagree, so please, just don't bother.

I actually completely agree with you, provided it’s the same reasoning. I feel cruel adding fish to small tanks as permanent homes. I believe it is okay to breed certain fish in smaller tanks like 20 gallon or 10 gallon, and I also don’t use that rule for certain species which naturally live in tiny bodies of water like betta splendens.

The same concept applies to me not buying predatory fish or most forms of MFK (however I do really want to get a dwarf channa in a 125 gallon). I don’t belive it’s right to put a predatory fish that hunts/marks a large area in the wild, such as arowana, gar, and the such in a confined tank with fed meals whether live feeders or dry food. Schoolers, cichlids, and labyrinths all the way.

 

[GaryE25 140]

Of course, smaller is easier. I just don't believe in small aquariums. I would never own, or recommend, anything smaller than a 40 gallon long for most species commonly found in an LFS. I fully realize the vast majority of people on this forum will disagree, so please, just don't bother.

I'll bother, simply because you told me not to!

It's all fine to make a strong statement and order people not to respond to it, but I'd like to read your logic. Lots of people believe in things, but discussions come from them sharing the thoughts that got them there. I'll give you some points to refute.

Bear in mind I generally don't keep standard LFS fish, but do have quite a number of common species.

I keep small killifish that aren't active swimmers and that breed well in single species tanks of 10 gallons. Many keep them in smaller tanks, but that would only be for egg collection in the short term for me. I prefer 20 gallons for them in groups, and tens for pairs.

I follow a self imposed rule that the tank I keep a fish in should have a front glass 8 to 10 times the total length of a full adult example of the species. By that rule, I won't keep any fish over 15cm because I don't consider it to have enough room to thrive in captivity. My largest aquarium is a 6 foot (72 inches/180cm), therefore, my largest fish will eventually reach 14cm adult total length. I stock lightly.

My largest tetras range at about 4cm.

Groups of fish from the Corydoras group do perfectly well in single species 30 inch tanks, often with a killie or a pencil to occupy the surface zone.

If you run community tanks or want larger fish, I can see cogent arguments against smaller tanks. However, in a world where space is expensive and many aquarists are fascinated by micro fish and shrimp, there's plenty of space for smaller tanks. I don't keep Cichlids, corys, or mid sized shoals of tetras in 10s - they are too small. Anything below 10 gallons is a temporary container to me. I like the 30 inch tanks I make for those fish, with 24 inch tanks, lightly stocked, as a minimum. I also have 40 longs, 75s, etc, for groups and communities, so it's possible I can understand your blanket statement.

Locally, my 2 functional lfs only sell microfish. It's an interesting trend. Smaller aquariums seem the future of the hobby, if indeed it has a future. So let's have some background for your strong statement, @kwamjing What are the fish you keep? What motivates you to say we need at least 40 longs?

 

[SammyTargo]

so it's possible I can understand your blanket statement.

In my opinion, I completely understand his statement, but there are some exemptions.

Some fish live in small muddy puddles in the wild...

Some examples:

• B. Splendens live in rice paddies and small puddles that allow them their own territory. Other betta species also may not live in exclusively puddles, but they don't leave their territory (which unlike cichlids, don't necessarily fight over "best" territories, they just need surface area to build a bubble nest and space from other males).
• Nothobranchius Spp. are literally the pinnacle of adaptation to puddles. Annual killis are called annuals because they only live around one year in the wild. I don't keep killis (I never got around to them, but they are amazing fish!), but I think they ironically live around the same lifespan in captivity despite not drying up. Killis have adapted what I call the triops niche, (which you may know what a triops is, but it is a small crustacean that is from prehistoric times and still lives today) which means that they lay eggs that can survive when dried up and will hatch once in contact with moisture. They are made to live in small water bodies, including tanks.
• D. Rerio also live in smaller bodies, primarily shallow pools and rice paddies in the Indian subcontinent, so they are fine in a 20 gallon, I wouldn't put them in a 10 because its not right to have schooling fish pace instead of swimming naturally.
• Poecilia velifera (Yucatan Sailfin Molly) is one of the fish that I have actually observed in the wild. A few years back on my trip to Mexico, I saw groups of these guys on the border of the river while I was swimming through a mangrove river into a basin that opened to the atlantic- great snorkeling in the reefs nearby by the way... Xcaret Xel-Ha if anyone is going to Mexico. I wanted to include them as I observed that although they had ample space to swim around, they all ended up sticking to their specific root-complex establishment. They do get bigger though as far as I observed, some even reaching what looked like to be 6.5 inches at mature females when pregnant, so probably not for a small tank but they do stick to their own area.

By that rule, I won't keep any fish over 15cm because I don't consider it to have enough room to thrive in captivity.

Completely agree, I hold a possibly even tighter standard of not keeping any species that are smaller than that, but cover large distances in their natural environment. To put a gar in a confined space where it should be swimming around to find food is torture in my books. A freshwater stingray is mistakenly described as a "bottom dwelling fish that waits for prey," which is not the case for their total annual behaviour; during the rainy season they track lots of ground across their river network to forage and express their seasonal behaviour. The difference between these examples and something like a datnoid, is that datnoids create a territory for themselves which they stay to for long periods of their lifespan and won't venture far in their natural environment making it acceptable to keep a large predator like that in a sufficiently (generously*) sized tank.