Tank advice

Not sure if i have put this in the right chat but i currently have a 55L tropical tank and am loving it but i want something a shallow like maximum 25cm tall only like a 20L or so but im struggling to find any tanks, anybody got any advice?

There’s not much you can keep in 20l, what are you thinking of putting in it? Dennerle do nice nano cubes and most brands have a 27l ish range. Aquastart 320 for instance, and they’re on eBay all the time, cheap as chips Good for a betta or shrimp

I think the only thing you could keep in a 20L is bettas, shrimp, or maybe a couple ADFs. I guess you could possibly fit a small killifish in there if the tank is highly planted, I’ve seen it be done before but it has to be a smaller species, not like the golden panchax.

Even though i have had a tank for several years i dont overly have a lot of knowledge, in my 55L i have mollys, guppies and a couple of different tetras, i had some small puffers but they seemed to die after a month for some reason, these are all my favourites, as to wether they could go in a 20-25L tank im not sure, im not adamant on gettig a small capacity tank, it can be as long as it likes it just cant be any higher than 25cm, for space reasons and also for something a bit different rather than a cube although im not apposed to that either although that’ll mean a small capacity

Do you mean you want to put all the fish you list in this possible 20 to 25 litre tank? If so I have to tell you it won't work.

Mollies are large fish, they need a tank at least 90 cm (3 feet) long. They also need hard water.
Guppies need a tank of at least 40 litres. They also need hard water.
There are hundreds of species of tetra and most of them need soft water, unlike guppies and mollies. And even the smallest tetras such as ember tetras need 40 litres minimum. Tetras bigger than embers need bigger tanks.

Which species of puffer did you have that died? Some species need brackish water, and if you had these, this would be why they died.


The only fish I would keep in a 20 to 25 litre tank is a single betta, provided your tap water is not too hard.

No this is a completely new tank with new fish my current fish are staying where they are, I can’t remember what kind of puffer i had, i can only describe them as a darf puffer, they didn’t reach over 1cm in size sorry to be no help there but i would like to get them again if I found the cure fot why they died, basically i want a small tank but with some well layered and goodlooking lively fish but I don’t know if im asking for a lot there in a 25L tank, cheers for any help

I was worried that you wanted to transfer all the fish over

Depending on the hardness of your tap water - soft, a single betta or hard, a group of male endlers. Those are the only fish I would keep in a tank this small.

However, a tank this size would make a nice shrimp tank. Again, your water parameters would determine which species would be suitable.

If you don't know how hard your tap water is, that info should be somewhere on your water supplier's website. You need to make a note of the unit as well as the number, as they could use any one of half a dozen different units.

I live in a soft water area, I’ve never had shrimp before and don’t really know anything about them, how big do they grow and how active are they? Also are they just the same level of maintenance as my current fish? Thankyou

Also i have always been interested in frogs when i have seen them at the shop but not known about them either, do you have any knowledge on them?

If you have soft water your livebearers (mollies and guppies) will not be happy as they need hard water. Mollies in particular get sick easily if kept in soft water. And they are big fish which need a bigger tank than 55 litres.
Guppies are hard water fish but are more adaptable than mollies provided the water is not too soft.

African dwarf frogs would be OK in their own small tank. They do not go well with fish because they are almost blind and find their food by smell. By the time they get there, the fish will have eaten it all and the frogs will starve. There is an excellent write up of ADFs here http://www.fishforums.net/threads/african-dwarf-frogs.234165/ They should be fed on specific frog food, not fish food. There is another frog traded in fish shops, the African clawed frog, which grows much bigger and needs a big tank. (Shops often mis-label frogs. Dwarfs have eyes on the sides of their heads and webbing between the toes of their front feet; clawed have eyes on top of their heads and no webbing on their front feet)

Shrimps come in many species, and like fish they have different water requirements. If you want to keep shrimps it would be helpful if you could tell us exactly how soft your tap water is (look on your water supplier's website) and what the pH of your tap water is, both a freshly run sample and some that has been allowed to stand for 24 hours. The easiest shrimp is the red cherry shrimp which grows to about 2.5 cm max.



You have mentioned elsewhere about getting another 55 litre tank. Again, before we can suggest fish we need to know the actual number for your water hardness, and your pH.
Bettas (siamese fighting fish) should not be kept in a tank with other fish. They can become aggressive towards other fish, and other fish can nip their fins. They do not need tank mates and are best kept alone. The 20 to 25 litre tank you mentioned at the beginning of this thread would be perfect for a betta, on his/her own, or indeed a 55 litre tank provided there are no other fish.

I also have guarami and plattys, none of my fish seem distressed and i very rarely have deaths, sometimes the odd one but they don’t have a massive life span anyway right? I cant seem to find anywhere online my ph level other than it saying its soft, i live in blackpool uk, if thats any help, whats the perfect layering of a 55l tank?

Go to this website https://www.unitedutilities.com/services/your-water-supply/drinking-water-quality/ and type your postcode in the box and click submit. The next page will be full of data. (I used the postcode for the Spar shop in Bispham Rd) Attached to this post you'll find a screenshot for that Spar shop's postcode showing of the bit of the page you need - click on it to see it properly. You'll see that gives "typical water hardness" as words, and "hardness clarke" with a number. That hardness clarke number is the one we need.

Those results you got there are exactly the same as mine

If the hardness you get is approx 10 deg Clarke, that converts to 8 German degrees (also called dH) and 140 ppm - fish profiles use one of those two units.

To be honest, a 55 litre tank is not that big. It will not be easy to stock fish in 'layers'. Most of the fish suitable for a tank this size are shoaling fish, and because they need to be in a group of at least 6, with more being better, there won't be room for more than one or two shoals. I used to have a 54 litre tank, so I know how small they are from a fish's point of view.
You need to look at fish that grow no bigger than to to 3 cm, and fish that 'pootle' around rather than dash around.

How long is the tank? Some tanks, like my old 54 litre, are long and not very tall. Others are not very long but are quite tall. The length of a tank is important as this provides the swimming room. Pootlers can be kept in shorter tanks than dashers.

I have the 55L aqua one aquarium which is 40cm cubed, and this is the tank i was thinking of getting again to match, starting to not want a 25L anymore and stick to what i have