How many fish?

LostBear

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We have just re-started fish keeping after about 30 years. Our new tank is 64l and approx 60cm x 35cm x 40cm (height). We set it up and cycled it four months ago, and when it was comfortably established introduced 6 rather sick-looking glowlights from Pets@home (I know, I know - we had a coupon). Last week we put in half a dozen neons. All the fish are doing very well. The glowlights, which were very dull two nd a half months ago, have developed really lovely red stripes, and have grown a lot - I'd say they are about 2cm, which I think is adult size. The neons are still small, obviously, but already their colour is improving.

We would like to add more neons (keeping it as a tetra tank), and I would like something to clean up the algae (the plants are suffering) and maybe tidy the tank bottom. Previously we had a little shoal of otocinclus, which are a delight, and a two corydoras, but the old tank was a 4 foot one and much bigger than the current one (we are already regretting getting such a small tank - we didn't realise we'd get sucked back in to the obsession so easily).

Can anyone suggest what would be best to do? I don't want a loach because they can be aggressive (and grow big). Is there any other general fishy cleaner that would be non-aggressive, but content to live singly? Would I be better with a couple of prawns? (Never had these, but they look very sweet). And how many more neons could we add, to keep not just safely, but healthily and with a decent quality of life for the fish? I'm not keen on stocking to the "max", but would like more if possible. Also - though we were intending just neons, I did wonder if a sort of "show point" fish would be nice to draw the attention among the little ones. Are there any you could recommend?

P@H tanks come with a "fish points" recommendation, but I
a) have no idea what they really mean (and nor do the staff at P@H)
b) I can't remember how many "fish points" the tank was supposed to support.
c) I don't have any faith in P@H advice anyway

I suspect that this tank will ultimately become a quarantine one for new fish, or a show tank for a betta, and that we'll get a bigger one, but at the moment we haven't a space for a larger aquarium.

Any suggestions will be much appreciated. Thank you.
 

Essjay

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Ignore that points system, it's rubbish. And so is most of the advice from P&H.

You will no doubt be asked by other members for the hardness of your water. Northumbrian Water don't give numbers and their words are misleading. If you do a search on their site for hardness, it'll probably say something like slightly hard - that's what mine says and it's actually 5dH which is soft.


Having got that out of the way, what do you have on the bottom of the tank? If it is sand, a shoal of one of the dwarf cories would work. Pygmy cories are the most common in shops, and I have seen habrosus (salt & pepper) cories at Maidenhead Aquatics (that's better than P@H but their advice can still be rubbish). But these are small fish which need sand or fine smooth gravel. With these fish you would need at least 10.
But cories are not algae eaters. Otos need to be in a shoal and 60 litres won't provide enough algae for a whole shoal of otos.

Some algae is normal in tanks. It's when it gets out of control that it's a problem. The main cause of algae is an imbalance between nutrients and light. Do you have live or fake plants?
Shrimps and snails do eat some types of algae, but nothing eats every type. Red cherry shrimps are the easiest type, but shrimps must have somewhere to hide - because they have a hard exoskelton they have to shed their skin to grow and while the new skin hardens they are very vulnerable. Nerite snails are also good algae eaters. (You'll read about mystery or apple snails but we can't get them in the UK becuase of EU legislation banning their import)



I would give serious though to increasing the shoals of the two tetras, especially if you go for shrimps and/or snails rather than dwarf cories. You could go up to 10 each.
Centrepiece fish don't usually work in small tanks. Maybe a pair of honey gouramis?
 
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LostBear

LostBear

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Many thanks for your very helpful reply, EssJay.

How can I go about testing the water hardness - I know that our water is soft, but I don't know how soft. We have an API testing kit (the test tube one - not the strips) which we use to keep a check on the water condition.

We have natural 3/16 inch aquarium gravel on the bottom of the tank (by natural I mean the sort of stuff you'd see on a beach - I'm not a lover of the brightly coloured, large gravel chunks you can buy - I like a more natural looking tank. I know that catfish of all types prefer something softer to root around in and that this would probably be too rough for many of them.

All of the plants are real ones - twisted vallis, ludwigia and another more ferny one, which I'm afraid I can't remember the name of. All three types are nicely established and have put out runners. I have cut them back once because they have got very leggy, and were starting to get covered with algae. As a result they're looking a bit tatty at the moment. I wanted some Java fern but haven't been able to get hold of any locally - might order some online. And what are the moss balls like? Do the fish like them, do you know? Any recommendations for plants would also be lovely.

The lights are LED - and I think I've probably been overfeeding and the excess has caused rampant algae growth. I don't mind a bit of green algae on the back glass, TBH, but it's clogging the plant leaves and is very unsightly - I use on of those razor blade cleaners to disperse it before water changes (have only done two of these up to now.)

I'm going to take your advice and stick to tetras - this was out initial intention and it looks like it's the best option anyway. And I'm going to try to get a couple of prawns and a snail or two. My only concern with snails is that you can end up over-run with the little beggars!

Thanks once again.
 

Essjay

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Get nerites! The females may lay eggs which look like sesame seeds but they don't hatch. Nerite larvae need salt water. These snails cannot over run a tank. There are several species which come in different sizes and different colours.

Algae is caused by an imbalance of light and nutrients. Too much food; too little food; too much light; too little light. The thing is working out which one is the cause.
Do you use a plant fertiliser - which one and how often?
How long are the lights on for?


I have Northumbrian Water pdf containing hardness for the whole region. It is rather old now and mine is 1 dH higher than it used to be but it will give you an approximate hardness. I'll send it via pm.
You can buy testers for GH but as hardness doesn't change by very much, you'll only use it once.
 
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LostBear

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Thank you - I'll certainly be looking into nerite snails.

I've checked the table you sent me. This gives:

Hardness - 7 (slightly hard) and

kH of 111

Not using a plant fertiliser. Lights on 12-14 hours/day, which I think is too much perhaps. (We forget to turn them off). I'm feeding a pinch of fish flakes twice daily, with occasional frozen daphnia.

Do you know if there are any places in the North east I could buy live daphnia? I know I can get them online, but I like to shop in person when I can (and now restrictions are lifted a little, it might be nice to have a look in an aquarist's).
 

Essjay

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Put the lights on a timer. You can get them at B&Q etc. The lights should be on at the same time of day for the same length of time every day.

I would start at maybe 10 hours or a bit less. If the plants start to go leggy, you can increase the number of hours; if they are still growing actively, reduce the time by an hour.
Don't overfeed the fish as uneaten food decomposes to ammonia which will feed the algae as well as the plants.
I'm not a plants expert, so I'll leave suggestions for plant fertiliser etc to those who know more. I have only slow growin plants attached to wood, and water sprite as a floating plant to I use only a small amount of liquid fertiliser (Seachem Flourish Comprehensive Supplemet at half dose). Plants rooted in the substrate usually do better with root tabs.

I don't know about live daphnia, I've always used frozen. But you could try Maidenhead Aquatics.



The hardness of 7 German deg is the same as dH; the other unit used in fish keeping is ppm and 7 dH converts to 125 ppm. This is fine for the fish you have, and shrimps and snails.
 
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