Advice About Adding Oto's Please....

[Mr Bee]

I originally posted this in the Characin section by mistake.... Ooops!!

So I'm re-posting it in here, as there may be more catfish people reading it

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Following on from a previous thread here about something to help keep my tank clean, I am leaning towards maybe adding some Oto's.

I think a BN (although lovely) may be a bit big at their full size, as are apple snails, and so I think the best option is to add some Oto's as they only grow to an inch or so.


I just wanted to ask and check a few things though.....

1) My tank is fairly small (60L or ~13 UK Gal.) and I currently have 5 Neon and 6 Glowlight Tetras in there. Will adding some Oto's be ok? - I'm thinking in terms of general bio-load, and oxygen usage, I don't want to be overstocking.

2) I've read they are best kept in groups as they are not happy on their own - how many could I accomodate in my tank, would 2 or 3 be ok; both for stocking and for their happiness?

3) I get mostly brown algae in my tank, will Oto's eat this?

4) How do I keep them healthy, happy and well fed - is adding algae wafers and veg like courgette (zucchini), green beans, peas etc. a good idea, and do you remove it after they've spent a few minutes eating it or anything??

5) I've got gravel substrate, would they just munch along the top or would they dig into it?

6) Do they need any special requirements such as a place to hide under or in at night or anything?


Sorry for lots of questions, but I'm trying to find things out and do my research, and see if they are suitable before I actually go and buy any.



Original post is HERE

But please feel free to reply to either thread

 

[nmonks]

Following on from a previous thread here about something to help keep my tank clean, I am leaning towards maybe adding some Oto's.

You don't need any fish to keep your tank clean. Moreover, if you stop and think about it for a second, you'll see the logical fallacy: more fish, more faeces and ammonia, more nitrate, more algae. Basic science. Anyone who tells you a "fish keeps the tank clean" is talking rubbish. At best they covert a small amount of unsightly mess (say, green algae) into a larger amount of invisible mess (ammonia, nitrate). More fish means more food goes into the tank, and less oxygen in the water. So by all means choose algae-eating fish or bottom-feeding fish if you want them: but NOT because they'll clean your tank; they won't!!!

1) My tank is fairly small (60L or ~13 UK Gal.) and I currently have 5 Neon and 6 Glowlight Tetras in there. Will adding some Oto's be ok? - I'm thinking in terms of general bio-load, and oxygen usage, I don't want to be overstocking.

If your tank is too small for Ancistrus, it's too small for Otocinclus. Just to recap, Otocinclus are schooling fish from cool, fast-flowing streams of the llanos (periodically flooded prairies). They like shallow water, bright light, green algae, and lots of tiny invertebrates. They are very sensitive to poor water quality, low oxygen, high temperatures (anything above 25 C), high nitrate, fluctuations in pH. You'll have a tough enough time keeping these parameters in a big tank, let alone a small one. Be under no illusions: these are not small fish for small tanks. They are small fish with big demands, and that's why their mortality in aquaria is hideously high. Easily 90% of the specimens sold die within a few months of being brought home.

2) I've read they are best kept in groups as they are not happy on their own - how many could I accomodate in my tank, would 2 or 3 be ok; both for stocking and for their happiness?

Absolutely not. You need at least six specimens. These are schooling fish. When kept in too small a group they almost always pine away.

3) I get mostly brown algae in my tank, will Oto's eat this?

Not really. They might nibble at it, but they can't survive on it. They feed on aufwuchs in the wild; green algae combined with tiny invertebrates. Since you have diatoms as the dominant algae type, you have too little light in your aquarium.

4) How do I keep them healthy, happy and well fed - is adding algae wafers and veg like courgette (zucchini), green beans, peas etc. a good idea, and do you remove it after they've spent a few minutes eating it or anything??

They'll eat algae wafers and very small invertebrates like mini bloodworms happily enough. They don't necessarily compete well with other bottom feeders though. They easily go hungry in tanks, and that may be why so many specimens "turn rogue" and nibble on the flanks of slow moving fish. Been there, done that.

5) I've got gravel substrate, would they just munch along the top or would they dig into it?

They won't care.

6) Do they need any special requirements such as a place to hide under or in at night or anything?

They are incredibly difficult to maintain. Read up on these fish carefully before wasting your money on them (which to be honest is what happens when most people buy them). If you want a small algae eater, I can't recommend highly enough nerite snails. They do a superb job on green algae, diatoms, and to some degree hair algae. They don't breed in aquaria, and don't add much bioload to the filter. Add a few cherry shrimps as well, and you're laughing. In my own tanks this combination works very well, to the degree I'm cleaning the front glass once every couple of months, if that.

Cheers, Neale

 

[Mr Bee]

OK, thanks for the info so far, but now I'm confused .......

After reading the reply from nmonks, I get the implication I shouldn't add Oto's, but Nerite snails or Cherry shrimp would be better.

So now I dont know what to add

1) Oto's (2 or 3)

2) Nerite Snail (? how many)

3) Cherry Shrimp (? how many, 2 or 3 maybe)


Yeah, I do want something that might keep some of the algae down, mainly on the rocks and decoration, as the glass is easy to clean anyway. Its the rocks and plants (synthetic plants) that I cant keep clean and they're covered in brown algae. So something to reduce or eliminate this would be great, as well as a bit of variety and something different too.


Oh, if its important, the tank has been set up for about 8 months, with my current Fluval 2 filter being in for the last 2 months (after my original filter packed up), but I moved the media from the old filter into my new one. And all the substrate is the same, so it should be a fully mature tank.

 

[nmonks]

1) Oto's (2 or 3)

None, in my opinion.

2) Nerite Snail (? how many)

I'd get at least three.

3) Cherry Shrimp (? how many, 2 or 3 maybe)

These are gregarious animals (not sure "schooling" applies to animals that walk about!) so get at least six.

Do understand that diatoms are notoriously difficult to eliminate, though nerites certainly will eat them. Diatoms grow in tanks with low light levels and often (but not always) poor/variable water quality, which is why they are so strongly associated with newly set-up tanks. While I'm assuming your tank has good water quality by now, you may well have low light levels. Most "algae eaters" go for green algae, which only grows under bright light. As has been written many, MANY times, the best way to deal with algae is to ADD more light, so that fast-growing plants can grow. Once they're established, you will find green algae become dominant, and it's these that the algae eaters eat best.

Cheers, Neale

 

[Mr Bee]

Ahh, I always assumed any algae was caused by exposure to light, didn't realise that too little can cause it too.

So, given my tank size and current set up (11 tetras) would you recommend adding 3 snails, 6 Shrimp, or 3 snails AND 6 shrimp together??


Also, I've been reading up on Nerites and Cherry shrimp, and it seems shrimp breed quite readily ("like rabbits" one forum said!); will this become an overpopulation problem, or will the filter and tetras 'remove' any baby shrimp before they get out of hand?

I don't want to end up with a tank full of hundreds of shrimp!


I know I keep going on and asking questions, but I want to be sure I'm doing the best, and most suitable thing for my fish and anything new

 

[nmonks]

Ahh, I always assumed any algae was caused by exposure to light, didn't realise that too little can cause it too.

Ah, you misunderstand me. Obviously all algae need light. But diatoms can get by with much less than green algae. So in a tank with low light levels, diatoms tend to predominate. Because few algae eating fish eat diatoms, the problem "looks worse" even though there might to be that much algae in real terms. In a brightly lit tank the green algae might be growing faster and in much larger amounts, but it's being constantly eaten by the algae eaters so you don't notice it so much.

So, given my tank size and current set up (11 tetras) would you recommend adding 3 snails, 6 Shrimp, or 3 snails AND 6 shrimp together??

Either or both. Provided the filter is reasonably good they won't have much effect on the water quality.

Also, I've been reading up on Nerites and Cherry shrimp, and it seems shrimp breed quite readily ("like rabbits" one forum said!); will this become an overpopulation problem, or will the filter and tetras 'remove' any baby shrimp before they get out of hand?

Nerite snails rarely, if ever, breed in freshwater tanks. They lay lots of eggs, but the larvae need brackish/salt water to develop. Without that, the larvae die. Cherry shrimps can breed quite quickly, but that depends on the juvenile shrimps not being eaten first. It's doubtful they will get out of hand.

Cheers, Neale

 

[Mr Bee]

Hi again,

OK, I'm half decided on getting some shrimps first, and maybe adding a couple of snails later.

But a few LFS I've tried so far dont sell them. You can get them online, but they all sell them as young ones at about 1cm big. I'm worried that at this size my tetras will either eat or harass them, and they will end up not surviving


What is your opinion, would 1cm Cherry Shrimp survive with my tetras, are they already too big to be attacked at that size?