New to Hobby, interested in starting to keep fish

Before you start deciding on substrate, you need to know the intended fish species. Some have requirements when it comes to substrate.

And consider the fish, not your perceptions, when it comes to what goes in the tank. White sand is not good; the light reflected off it will detrimentally affect fish. It is also not as easy for us to view a tank with white, I realize this every time I come across one. Fish have expectations programmed into the species DNA that must be understood and accommodated if we want healthy fish.
 
Like I said "nothing is set in stone"

I found the idea of sand and black gravel on youtube. I liked the look of it - the contrast between the black and white, and having a few different species of plant seemed great. She had snails and some fish in a 20 gallon tank. But now moved on to a tank with betta's. Let's forget I said anything about sand.

Moving on.

I'll consider these fish from South America/Asia
  • Sparkling Gourami
  • Honey Gourami
  • Cherry Barb
  • Corydoras Catfish, unsure which species
  • Kuhli loach
 
The thing to consider about substrate is that certain fish, particularly sucker mouth catfish types, need to have very fine gravel or sand. If you use big lumpy gravel it can hurt their delicate mouths.

Other types of substrate may contain substances that are unsuitable for shrimp. Usually it is the pre-fertilised types but they are generally labelled as "shrimp safe".

If the tank is going to be quite well planted and you want to make a sort of 'river of sand' then it won't be a problem. It's when people put white sand all over the tank and choose fish that are from dark rivers and streams.

Think of it this way. If the water was crystal clear and the ground was white sand in their natural environment then why would they evolve into bright neon blue colours?
 
Not too bothered about the sand it was only an idea. I have over 20 years of going fishing in real life, so I do know a thing or two about fish, but not keeping fish as pets.

Yes I know about certain fish hurting themselves on certain gravel. I've been reading a lot on the net.

If there's any more fish I could consider, please feel free to write them down. There are discus but they grow large and too advanced for me, so they're out

I would like to know how many fish would fit in a 20 gallon, depending on the size of fish I get?
Also, other easy to keep plants with the ones above.
 
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Not too bothered about the sand it was only an idea. I have over 20 years of going fishing in real life, so I do know a thing or two about fish, but not keeping fish as pets.

Yes I know about certain fish hurting themselves on certain gravel. I've been reading a lot on the net.

If there's any more fish I could consider, please feel free to write them down. There are discus but they grow large and too advanced for me, so they're out

I would like to know how many fish would fit in a 20 gallon, depending on the size of fish I get?
Also, other easy to keep plants with the ones above.
Well my best advice would be to pick a favourite species and then build around that. Kind of like selecting a football team.

All kinds of tetra would be perfect in a 20 gallon tank. I would select your favourite looking species and buy loads of them. They behave so much better in large groups.

Many people will just buy 6 neon, 6 rummy nose, 4 guppys etc and have a muddled up tank and miserable inactive fish.

A group of 20 neon tetra will school up much tighter than a group of 6 or 10. They will clump up and dash about in a big swarm and I find that far more impressive than a small handful of everything.

Corydora do the same too. If you could get a reasonably sized group of tetra and a similar sized group of dwarf corys then you would have a really active tank. The corys would school up at the bottom and soft around the substrate in a big swarm and the tetra would be clumping up in a tight group and dashing around the tank.

Corys also are less bothered about species so you could get dwarf and pygmy and put them together. Neon tetra will only school with other neons.

That's how I would do it. Kuhli loaches would tend to be occupying the same space as corys so I would give them a miss. Also the others are South American do now you have an excuse to do an Asian tank haha.

A good Asian themed rank might be

Top - Gourami
Middle - Harlequin Rasbora
Bottom - Kuhli loach

Easy Asian plants, if you're that keen would be java fern and moss along with cryptocoryne.

South American plants would be Amazon sword and cabomba for example
 
I would like to know how many fish would fit in a 20 gallon, depending on the size of fish I get?

This is a question frequently asked, but one that is difficult to answer easily. I will attempt to explain.

While fish mass (size) obviously impact the tank's biological system, there are several other factors that also do this. As a starting example, in your 20 gallon, a group of 15 Zebra Danio would have significantly more of an impact than a group of 20 cardinal tetras even though these fish are roughly the same size. This means the cardinals would be OK, the danios definitely not in this sized tank. Room to be themselves is one aspect; active swimmers like the danio need more space, and without it they are stressed and this impacts the system.

Numbers of a species also impact the biology, but not just in too many; too few can be negative too, because this again stresses the fish so there is a greater impact.

Having non-compatible fish/species can make a big impact, and this is not just thinking of aggressive/peaceful but several other aspects.

Another example, a 20g is not sufficient space for Tiger Barbs. One might think that six or seven of these small fish would bee OK, but they would not, and they would not live all that long in such circumstances. This is a species that must have 10-12 minimum, in a 30 gallon tank, as the minimum.

The aquascape impacts too; if the fish in the tank are all suited, to the space and each other, and if they then have a habitat-relative aquascape, they will impact things much less than if they are in an inappropriate aquascape. Water parameters factor in too. Along with light, filter flow...almost every aspect is part of the overall biological system.
 
Well my best advice would be to pick a favourite species and then build around that. Kind of like selecting a football team.

All kinds of tetra would be perfect in a 20 gallon tank. I would select your favourite looking species and buy loads of them. They behave so much better in large groups.

Many people will just buy 6 neon, 6 rummy nose, 4 guppys etc and have a muddled up tank and miserable inactive fish.

A group of 20 neon tetra will school up much tighter than a group of 6 or 10. They will clump up and dash about in a big swarm and I find that far more impressive than a small handful of everything.

Corydora do the same too. If you could get a reasonably sized group of tetra and a similar sized group of dwarf corys then you would have a really active tank. The corys would school up at the bottom and soft around the substrate in a big swarm and the tetra would be clumping up in a tight group and dashing around the tank.

Corys also are less bothered about species so you could get dwarf and pygmy and put them together. Neon tetra will only school with other neons.

That's how I would do it. Kuhli loaches would tend to be occupying the same space as corys so I would give them a miss. Also the others are South American do now you have an excuse to do an Asian tank haha.

A good Asian themed rank might be

Top - Gourami
Middle - Harlequin Rasbora
Bottom - Kuhli loach

Easy Asian plants, if you're that keen would be java fern and moss along with cryptocoryne.

South American plants would be Amazon sword and cabomba for example

Thanks for the post, I needed some guidance.

I think I would go for the Corydoras not the Kuhli's.
Rummy and Neon Tetra? 10 of each? Or one species only with so many Cory?

Although I said in a previous post that I didn't want tetra, I've changed my mind. I'm guessing they're a good for beginners.

This is a question frequently asked, but one that is difficult to answer easily. I will attempt to explain.

While fish mass (size) obviously impact the tank's biological system, there are several other factors that also do this. As a starting example, in your 20 gallon, a group of 15 Zebra Danio would have significantly more of an impact than a group of 20 cardinal tetras even though these fish are roughly the same size. This means the cardinals would be OK, the danios definitely not in this sized tank. Room to be themselves is one aspect; active swimmers like the danio need more space, and without it they are stressed and this impacts the system.

Numbers of a species also impact the biology, but not just in too many; too few can be negative too, because this again stresses the fish so there is a greater impact.

Having non-compatible fish/species can make a big impact, and this is not just thinking of aggressive/peaceful but several other aspects.

Another example, a 20g is not sufficient space for Tiger Barbs. One might think that six or seven of these small fish would bee OK, but they would not, and they would not live all that long in such circumstances. This is a species that must have 10-12 minimum, in a 30 gallon tank, as the minimum.

The aquascape impacts too; if the fish in the tank are all suited, to the space and each other, and if they then have a habitat-relative aquascape, they will impact things much less than if they are in an inappropriate aquascape. Water parameters factor in too. Along with light, filter flow...almost every aspect is part of the overall biological system.

Yes, I realize the surface area of plants and decorations will have an impact on the quantity of fish I would be able to fit in a tank. Of course, I do know I cannot have large fish in a 20 gallon.
 
Found this website which could be good for seeing how many fish can fit into a tank (I know plants/ornaments are not included.) It has a list for different filters used and I don't know what kits use.

AqAdvisor

Unsure which Cory I could get, I think it would depend on what my local shops have.
 
Found this website which could be good for seeing how many fish can fit into a tank (I know plants/ornaments are not included.) It has a list for different filters used and I don't know what kits use.

AqAdvisor

Unsure which Cory I could get, I think it would depend on what my local shops have.

AqAdvisor is not bad as far as it goes, but it cannot possibly be totally reliable because it cannot consider all the factors. Those things I mentioned previously in post #21 require human thought.
 
Which 20 gallon would be good? The tall or long model?

Given fish like those you mentioned previously (post #17) the 20g long would be better. The "footprint" which is the surface area of an aquarium is more important than how much volume it holds, generally. The gas exchange at the surface is critical, and obviously the floor space can affect territories and swimming activity.

While you are looking at 20g long, which is 30 inches length by 12 inches width, the 29g has the same footprint but slightly higher for the additional volume. I chose this over the 20g long and now have two of them, as this is a quite useful tank.
 
I've scoured the net for stores that have websites and none of them have any 20 long tanks.
I'll keep the 29 gallon in mind.

Any ideas on companies that do good kits?
 
I've scoured the net for stores that have websites and none of them have any 20 long tanks.
I'll keep the 29 gallon in mind.

Any ideas on companies that do good kits?

If by kits you mean a complete tank with the equipment, I've no idea what might be available in the UK. But I tend to avoid these, as I prefer to find a suitable filter and heater depending upon the fish I intend, rather than the "stock" equipment (often of poorer quality) with packages. The only exception being that I will sometimes buy a tank with a cover/light/hood, since it can sometimes be tricky finding the lighting, but only if I know the lighting is good with the package.
 
Found it diificult in finding a tank I want. Finally found one and decided to get the 20 gallon 'long' instead of the 29 gallon. Sadly I would have to order it online and risk breakages. But I'll try and find a store close by.

Been watching and reading a lot and I'm not in a rush in getting a tank.

I don't want to spend too much at the moment, because the fish will be fairly expensive.

Any recommendations on S.American oxygenating plants? 'TallPaul' mentioned the Cabomba, but this grows around 1" per day, not too keen on it, but will keep it in mind and I'll have it as a choice. I'll add the Amazon Sword on my list too.

Unsure what filter I should buy?

Substrate will be fine gravel (for the cory's) unsure about colour, maybe black. I'll feed the plants with Seachem Flourish Tabs or similar.

Heater and API test kit are on my list
 
Unsure what filter I should buy?

The filter depends upon the intended fish. Some fish need a stronger current, some none at all or very little, and this is largely the filter's job. Also, with plants there is less need for significant biological filtration, and no chemical filtration at all (carbon, etc). So a tank of say small tetras and cories would be fine with a dual sponge filter. All of my tanks under 40 gallons have a dual sponge filter.

Any recommendations on S.American oxygenating plants? 'TallPaul' mentioned the Cabomba, but this grows around 1" per day, not too keen on it, but will keep it in mind and I'll have it as a choice. I'll add the Amazon Sword on my list too.

All plants are oxygenating during "daylight" [daylight here means when the tank lighting is on] with faster growing plants obviously producing more than slower growing, just as they take in more/less CO2 and nutrients proportionally. Cabomba is a fairly fast growing stem plant (most stem plants are), but this also means more light to drive photosynthesis, and more light means more nutrients. Fertilizers can add some, but CO2 is basically whatever is produced naturally, and you have to balance this with the light. I am unable to grow Cabomba, after a few weeks it begins to fall apart, primarily because my light is not bright enough.

My choice in fast growing/oxygenating plants are floating plants like Water Sprite. Being under the light, they usually have no light issues. Being at the surface they can assimilate CO2 from the air which is four times faster than submersed leaves. And oxygen is diffused through the dangling roots.
 

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