Hi, I only joined today,
I've been thinking of adding to My talk
But first wanted to make sure it wouldn't be over stocked
At present I have
1 x blackmoor
1 x fantail
1 x weatherloach
6 x snails

3 plants and a 6" aeration ornament

I'm wanting to add
1 x weather loach
2 x sucker fish

My tank is 40 litres
And has a fluval 3 filter

Any answers and comments would be really helpful thank you!

Hello, everything depends on a couple of different factors really ie how big are the current fish? Also what type of Snails are in the tank?
Personally I think all of the "rules" about how much space a fish should have are a load of old nonsense, you should just use your common sense. Bare in mind that more fish means more mess regardless of the filter and snails (which eat algae and left overs). The fish need enough room to not get in each others way and have enough room to swim properly so use your digression baring in mind adding more fish could cause problems, you wouldn't want any of your other fish dying!

Hi,
I'm no expert, but according to the caresheets on here your tank is too small for the fish you've already got

Black moors need 140 litres, as do fantails. They also need more space for each extra individual, and weather loaches need at least 300 litres. Also, the fish you've got are quite messy and so produce a lot of ammonia which is toxic. If your tank is cycled, this will be converted to nitrates, which are less toxic but bad in high concentrations, and due to the small tank size the concentrations will rise very quickly and leave the fish more susceptible to disease. If your tank isn't cycled or the filter can't cope with the current bioload, ammonia levels will quickly rise and could kill your fish. Looks to me like you need to rehome the fish you've got or buy a much larger tank to stop problems from developing, but I'm sure an expert will be able to help you more than me.

Good luck

I'm no expert either but when I read the care sheets which say 140 litres for a black moor I'm like "say whhaaaa!?" I think my bath is only about 200 litres where as my old Black Moor (RIP) was only about 2 inches long! It doesn't seem logical when they are only young.

Hi

Your tank is very overstocked and at 40 litres is too small for any Goldfish or for Weather Loaches. Sucking Loaches are tropical fish so shouldn't be put in coldwater tanks even if big enough. They also grow very large and become aggressive as they age and aren't recommended in general commuity tanks.

The minimum tank size needed for Fancy Goldfish is 140 litres for just ONE, with 45 litres extra for each additional Goldfish and a tank at least 3 feet long. This article explains the requirements of Golfish in aquariums.

Weather Loaches need at least a 300 litre tank that is 4 feet long. They need to be kept in groups of 3 or more as they are a social grouping species and they must have sand as the substrate as they like to dig and hide in it.

Quote:

Tanks need to be sized for the expected adult size of the fish to give them room to grow properly, keep the water quality up (especially with messy fish like Goldfish) and give them room to express natural behaviour and live long and healthy lives.

An adult Black Moor should be around 8 inches long excluding tail and juveniles kept in the right conditions can be expected to grow from 1.5 to 3 to 4 inches in only six months, as this thread from Violet illustrates.

Thanks fishlady, you're like the human google! I've seen some massive fancy goldfish and would never dream of keeping one that big in my tank, I have mine in a 40 litre tank and am keeping an eye on its size, as soon as its too big I'll be moving it straight into a neighbours pond and will replace it with another smaller one, does this sound like a reasonable idea? Or will I be condemned by fish experts everywhere?

Well to be honest it's not a great idea for a couple of reasons. The first is that it will probably not grow as it should in a 40 litre tank and may well suffer stunting and/or a damaged immune system before you realise what's happening.

The second reason is that Fancy Goldfish can't live outdoors in ponds in the UK. They need warmer conditions than Common Goldfish and aren't able to cope with the colder winter weather. Most would simply die the first winter they were outside.

If you need to rehome a Fancy, it really needs to go to someone with a large tank.

Quote:

If you've got a succession of tanks to move them into as they grow then a 40L would be OK for fry, but you'd be rehousing them every six months or less. Goldfish do most of their growing in their first two years or so, and commons get anything up to a foot long. A 140L tank for a Black Moor is recommended as this will provide a home for life for one fish. As already noted if your Black Moor was only 2" long, it was very likely stunted.

The various recommended tank sizes are the size they are because of observations about the expected size and behaviour of the fish. Zebra Danios and White Cloud Mountain Minnows are a similar size, but Danios need much more space than WCMMs because they're that much more active.

Stocking levels are a little different, and bit more flexible and depend on the fish you have (predatory fish are very messy), their numbers, size, etc. Here the various "rules" are really only guidelines drawn up to ensure that you don't overstock a tank. The main thing that will limit how many (compatible) fish you can fit in a tank (that is a suitable size for them) is how fast your nitrate levels rise.

@ BadFootBill: I wouldn't recommend replacing the fish with a smaller one, you'll only have to rehome that at some point too if you can't upgrade the tank and while it may sound harsh your inability to house the fish you've purchased knowing that you're not going to be able to accommodate it at adult size should not really be someone else's problem Plus, if the fish is a fantail and by this I mean double tail and not a single tailed fish with a 'fancy' tail then it may struggle in a pond as the swings in temperature can play havoc with their digestive systems and potentially cause circulation issues in uber long fins which can then lead to fin rot problems.

At the risk of shameless 'self promotion' ... as far as stocking, and fish 'growing to the size of their tank' is concerned you may some info I put together for a web project useful:

http://injaf.org/articles-guides/unde ... ing-fish-stocking-guides/
http://injaf.org/articles-guides/do-f ... o-the-size-of-their-tank/