Stocking My 20 Gallon Tank

[Boulder Fish]

Short version..
I'm back at the beginning of a fishless cycle, so I have plenty of time.I'd like as many opinions as people want to share so I can do more research.

Mine is a 20 gallon tank (24" x 12" x 17"), with a sand substrate (EC under the sand for live plants), a few live plants (hoping to add more in the future), several decorative plants and lots of places to hide.

I chose the sand substrate to accommodate a few dwarf loaches (I am thinking 3? is 5 better?)

I also love the colors of the dwarf gourami, (though I am a bit worried about how prone to disease they sound)
Do single gouramis fair well in community tanks?

What other fish would make sense in this tank?

 

[Corleone]

5 dwarf loaches might be a bit much, at least early on. They do well in groups, and are quite small, but it's a good idea to stay inside the inch-per-gallon rule starting out. It'll help you avoid a lot of potential mistakes.

You should be ok with a single dwarf gourami. I rarely see females for sale in my area. They do generally do better in trios (two females to a male), though. They are sensitive fish and can be disease prone, but since you're doing a fishless cycle, you're in a good position on that front. Make it one of the last fish you add to the tank, after it's been established and stable for a few months, and you should minimize the risk.

A school of danios would also make sense. They tend to stick towards the top of the tank. I personally love pearl danios. Very hardy, and they put on a wonderful color show once they're settled in. Harlequin rasboras are smaller, and also tend to stick to the top.

Tetras or most of the peaceful barbs could work for the middle levels of the tank. I'd avoid nippy species like tiger barbs or serpae tetras, since the gourami has long feeler fins that are vulnerable to nipping.

Corydoras are one of the community staples. Nearly every community stocking you see involves a group, though with five dwarf loaches, you might not want corys. They'll require groups of 5-6 as well, and even going with small corys (pandas or dwarfs), the bottom will get crowded. They are great fish with a lot of personality for their size, though. They'll also appreciate your sand substrate.

I'd throw an apple snail, or maybe a couple nerite snails in, too. Both come in some attractive colors, and they're a good cleanup crew, and give you a bit of a safety net for minor overfeeding. Neither species is prone to runaway breeding, either. Apple snails have distinct sexes, and their eggs are fairly easy to spot and remove, and nerite snails rarely if ever reproduce successfully in fresh water, though they will lay eggs that may or may not hatch, you'll probably never see a baby snail. Even snails that will breed can be kept in control - snail survive on overfeeding, so if there's not enough to support more than a small population, you won't get more than a small population.

Shrimp should also work with the fish you listed and I've suggested, and are another low-bioload cleanup crew.

Obviously 20 gallons isn't big enough for everything I mentioned together, but there's a good deal of ideas for you to look into.

 

[Boulder Fish]

Thank you for your thoughts. I am definitely interested in a school of small guys to go along with the gourami and loaches.

Can anyone steer me toward compatible fish with yellow, orange or red?

 

[Corleone]

The pearl danios have a good bit of red in them. They're primarily pink, but their red really jumps out.

Platys and guppies come in all those colors (and about seven million others), too. They're very pretty fish, but watch out for breeding, as they reproduce prolifically in even the most borderline acceptable water conditions.

 

[Boulder Fish]

Thanks. I have been checking out the pearl danios, and they seem like a good option.

I figure I can get 5 in the tank with a dwarf gourami and 3 chain loaches. Is that pushing it in a 20 gallon tank if I am also thinking about shrimp and/or snails?

The pearl danio profile says they are easy breeders. How can I avoid having to raise fry if I choose a shoal of pearl danios, or even platys?

 

[rabbut]

The proposed stocking looks good to me

Danios are easy breeders, but you are unlikely to get many (if any) babies making it to adult-hood in a community tank. The other fish (including the parents) will eat the eggs and the fry before they get very late on in development

HTH
Rabbut

 

[Boulder Fish]

Thanks rabbut.

Does the same idea apply to platys? The fry would be consumed?

And would I need to stock fewer platys because they get slightly bigger than the pearl danios? Say, 4 platys OR 5 pearl danios?

Speaking of pearl danios, I went to my LFS today to see how they looked in person. They were in a tank with one other species of fish, all of whom were covered in white spots, and one of whom was dead. Of course, I am weeks away from stocking my tank, but, what do I make of this information? Most of the other tanks looked healthy (though I did see a dead dwarf gourami). Is disease in the LFS considered temporary and/or treatable, or is it literally the kiss of death?

Oh, and I almost forgot. I saw some cute little fish called galaxy rasboras. After checking here on the forum, I see these are the same as Celestial Pearl Danios. They are very tiny (only .75"), but gorgeous. Is it safe to buy these fish if they as long as they are tank bred? Or would I be perpetuating the demand, and further endangering them?

If tank breeding solves the ethical dilemma, then how many could I add or exchange with my proposed stocking (1 dwarf gourami, 3 chain loaches, 5 pearl danios OR 4 platys)?

 

[Boulder Fish]

Should I be starting a new thread to talk about the sick pearl danios and the ethics of the galaxy rasboras?

 

[Corleone]

Speaking of pearl danios, I went to my LFS today to see how they looked in person. They were in a tank with one other species of fish, all of whom were covered in white spots, and one of whom was dead. Of course, I am weeks away from stocking my tank, but, what do I make of this information? Most of the other tanks looked healthy (though I did see a dead dwarf gourami). Is disease in the LFS considered temporary and/or treatable, or is it literally the kiss of death?

The disease is probably ich ("whitespot"). It's treatable, though it's not a good sign to see it at the LFS, and I wouldn't buy anything from the same tank if I saw a sign of it. There's always a risk of bringing a disease home with a fish, which is why it's good form to quarantine all new fish for a month.

The celestial pearl danios are a complicated matter. Because they're endangered, there's a valid argument that if you purchase them, you should commit to breeding them and helping the species. They're a recent discovery, so I don't know if they're being commercially bred yet. If they are (or once they are), their status in the wild means somewhat less, IMO. Endlers are feared to be extinct in the wild, but are still a common aquarium fish, though there are concerns there about careless crossbreeding with guppies endangering what's left of the species.

If you were to go with them instead of pearl danios, you could almost double the number. Pearl danios are one of the better sized danios, around 2 inches. Celestials are half of that, I don't think they get much over an inch.

 

[rabbut]

Celestial danios are commercially bread, but still expencive. We have some that I would still consider fry at work, and my boss recons he can get £5.99 each for them

Yes, platies breed, but they drop larger fry that are better able to hide, so although most wn't make it, 1-2 of each laying will, and breeding monthly, you could easily double your numbers in a week, of you had a 3foot tank full of them

HTH
Rabbut

 

[rhostog]

Have you checked the pH of your water? I think most of the species mentioned above are fairly adaptable, but it might be worth checking that you don't have very acid or alkaline water.
I'd agree with Corleone about cories - they're real characters, especially if you have several, very busy, scrabbling around in the substrate, following each other around.
Platies are colourful, active and not aggressive, and you can even get them with Mickey mouse markings on their sides - what more can you ask for! Our female platy had babies the other day, just as we were going out. Although we've got quite a lot of plants and hiding places, by the time we got back, the zebra danios and platies were looking fat, and not a baby to be seen. Not that we had space for all of them, but I'd kind of hoped one or two would make it...

 

[Boulder Fish]

Yes, it appears I have expensive taste, which may redirect this potential stocking list.

The Celestial Pearl Danios are $9.99
The Chain Loaches are $14.99
The Dwarf Gourami is a BARGAIN at only $7.49!

Are Corydoras less expensive than the loaches? I was steering away from those because I "knew" a couple of upside-down catfish once, and all they did was hide. Perhaps other corys are more out in the open?

I like the looks of:
Corydoras sterbai (Sterba's Catfish?)
Corydoras aeneus (Bronze Cory)
Corydoras trilineatus (Leopard Cory?)

Anyone have any feelings about those?

The pH of my tap water is 7.6, and it is soft.

 

[rhostog]

The most popular corys are generally cheaper than loaches here in the UK. I think my bronze corys were about £1.50 each, and the leopards (trilineatus) were £3.50 each. I'd guess they'd be similar prices in the US? My bronzes are very active and spend a lot of their time in the open; the trilineatus are shyer and tend to hide more, but they do come out at feeding time, and they are very pretty. However, I've only got 2 of each, and they all seem to be happier in larger groups, so perhaps if I had more, they'd be more active. There are some threads in the cory section discussing how much different species will group together, and which species are generally shyer. They should be fine in your tap water, especially if you can find some locally which will be used to it.

There are several species labelled as 'leopard' - most common (in the UK at least) seem to be the trilineatus. You can also get julii, which look similar but have smaller, more separated spots on their heads. Trilineatus are often mislabelled as julii. To add to the confusion, mine were not fully grown when I got them, and their spots have joined up and darkened as they got older, so they started off looking like julii but turned out to be trilineatus. Not that I mind. Although they're quite shy, I think they're my favourites of the fish we've got.

I'd love some panda corys, they look really sweet, but my local water's not ideal for them and I don't want to risk losing them.

The chain loaches look really cute too, but I've only seen one, once, in one of my 4 local shops, and he didn't look very happy. I'd love to see a group of them.

I would say, your fish will hopefully be with you for quite a while, maybe several years, so if you can afford it, it's worth paying for the ones you really want, even if that means waiting a bit, rather than buying second best and then regretting it. Well, up to a point. My daughter really wanted a zebra plec...

 

[Boulder Fish]

I just read the latest reply aloud to my husband, and he totally agrees with you, rhostog.

He says that since I am spending all this time on fishless cycling and trying to do it right, I should get to have the fish I really want to look at.

SO, if I take that approach, what do I need to know about stocking this tank gradually? If I can only afford to add the 3 dwarf loaches at first, will they be ENOUGH of a bio-load to keep the tank cycled?

If I go with the celestial pearl danios, is it okay to add 5 one month, and then 5 the next month?

Based on earlier posts, it sounds like getting the gourami last, and a few months down the line would be smart.

Actually, this brings up another interesting question about quarantine. After reading several threads, it sounds like quarantine helps insure that disease stays out of my main tank. So, this means I should quarantine ALL my fish, even the FIRST ones I add to a newly cycled tank?

And, if so, do I wait until my fishless cycle is complete, then snag some of the filter media and water to start a quarantine tank before buying fish?

 

[Corleone]

I agree with rhostog and your husband, too - you're quite committed with the fishless cycle, and you're giving any fish you get a much better chance than many that leave the store get, you definitely deserve to get what you want.

As for "keeping" the tank cycled, the bacteria might scale back if you don't have many fish in the tank for a while, but it will stay cycled enough for whatever you have (with some buffer - the bactera need X amount of ammonia to survive, but will process somewhat more if its available, and will tend to grow until only X is available). If you only have the chain loaches for a while, you might have to got a bit slower with adding more.

With my pearl danios, I was able to add them in phases. I noticed when I first added some, they wouldn't school with the existing group, but they usually huddle together to get away from the commotion when I do a water change or clean the tank, and will eventually school together.

Don't worry about quarantining your fist fish, IMO, but treat your tank like a quarantine tank when you do add them - don't add anymore right away, and pay extra close attention for any signs of problems. After the first lot, quarantine any new additions.