New Oscar Tank

[Les Isaacs]

Hello

I am about to set up a 5 foot tank for an Oscar, plus probably a plec and a catfish (or other Oscar tankmates!). I have received various advice from experience fishkeepers about whether a 5 foot tank is OK for the Oscar, some of it positive and some of it negative. Overall, it seems that while bigger is always going to be better than smaller, a number of people have kept Oscars in 5 foot tanks with no apparent ill-effects (some have kept them in 4 footers), so I will be doing likewise (but with just one Oscar as opposed to my original plan for two!).

I already have a 4 foot tank with 14 various malawis and a plec, and intend to start off the 5 foot tank with around 40 litres from the existing 4 foot tank. I am hoping to obtain some mature media from someone from the list of people offering mature media for new tank setups. For the 5 foot tank I have an external fluval 303 and an internal fluval 4+.

Now the questions:
1. As I will be starting with just one small (young) Oscar, plus 1 or 2 plecs/catfish, and with some mature water (and hopefully media), would it be reasonable not to bother with the fishless cycling phase?

2. Would it be a good idea to sit the media from the external fluval 303 and internal fluval 4+ in my existing 4 foot tank? This media is currently used but dry: should I wash it first? Is there any possibility that it could harm my malawis?

3. Would it be better to start with the fish just in the 40 litres of mature water, or should I add some tapwater to this immediately, or some time later? If immediately, how much to add - another 40 litres, or a bit more than that, or enough to fill the 5 foot tank? Also, in addition to a dechlorination agent (which is the best one?), what would be a good maturing agent to add?

4. Any good suggestions for other Oscar-mates, apart from (i.e. instead of) plec and/or catfish?

5. I am a newcomer to this forum: is it OK to ask 5 questions in one post?!

Hope someone out there can help.
Thanks
Les

 

[Miss Wiggle]

Hi Les

few answers for you and some questions too!

my thoughts firstly......

what are the dimensions of the 5 foot tank, it's not just the length that's important but depth and width also.

don't bother moving water from your malawi tank, the oscar requires a different ph to the malawi's so they shouldn't use the same water. Also there's not really any such thing as 'mature' water, very little of the beneficial nitrifying water lives 'free' in the water, it lives in the filter media, this is the only thing you need to get from another tank.

1. As I will be starting with just one small (young) Oscar, plus 1 or 2 plecs/catfish, and with some mature water (and hopefully media), would it be reasonable not to bother with the fishless cycling phase?

no, if you just get mature water you may as well have got nothing. if you get mature media you can stock immediately, if not then you should do a fishless cycle. however as you already have a tank set up you don't need to worry about cycling, see below.

2. Would it be a good idea to sit the media from the external fluval 303 and internal fluval 4+ in my existing 4 foot tank? This media is currently used but dry: should I wash it first? Is there any possibility that it could harm my malawis?

get the filter for the new tank and just run that alongside the existing filter on your malawi tank for a fortnight then you can put it on the new tank and stock straight away. I'd get new media and start afresh if I was you.

3. Would it be better to start with the fish just in the 40 litres of mature water, or should I add some tapwater to this immediately, or some time later? If immediately, how much to add - another 40 litres, or a bit more than that, or enough to fill the 5 foot tank? Also, in addition to a dechlorination agent (which is the best one?), what would be a good maturing agent to add?

as I explained before, don't move over any water, mature your new filter as above, then fill the tank with declorinated water (we use API Tap Water Conditioner), transfer the new filter across, plug it in and start it up straight away, stock the tank the same day this is important as the filter bacteria will die off if you leave it a few days with no fish in the new tank.

4. Any good suggestions for other Oscar-mates, apart from (i.e. instead of) plec and/or catfish?
there are a number of options, basically other medium sized moderately aghressive new world cichlids should be fine. the one think that's really really important with finding an Oscars tankmates is that they should all grow up together. this will massivley reduce the chances of agression later, so you should decide on your full stocking list, get them all as juveniles within a few days of each other and let them grow up together.

5. I am a newcomer to this forum: is it OK to ask 5 questions in one post?!
yeah that's fine! i've got a thread 16 pages long and still ongoing cos i keep asking questions!

 

[Les Isaacs]

Many thanks for all this great advice!

I have now put the two filters that will be used with the new tank into my existing tank, so hopefully the appropriate bugs will now grow in them. Would one week be enough before I transfer the filters to the new tank and add oscar et al, or should I wait two weeks?

Although I (now!) understand that the bacteria is held mainly in the filters and not in the water, I was surprised that you suggest not using any of the water from my existing tank for the new tank. The pH in the existing tank is 7.6, which suits the malawis OK and I had though would be OK for oscar and friends. Is this not true, and if so is there any other reason why I shouldn't used the existing water?

Finally: decor. I have heard that slate is OK, but that bogwood should be avoided due to its sharp edges. Surely though slate has sharper edges than bogwood? Should I therefore just be looking at nicely rounded cobbles, plus something (plastic piping?) for the fish to hide in? Is it OK to use scrubbed and boiled cobbles from the garden and/or a local river (my lfs charge a fortune for them!)?

And absolutely finally, what about sand v gravel v sand-and-gravel: is there a 'right' choice?

Thanks again for the advice: it's literally invaluable.
Les

 

[Miss Wiggle]

OK I'd wait 2 weeks just to be on the safe side, fishkeeping should never be rushed

a ph of 7.6 is fine for the oscar and friends, but I'm dubious about it being alright for your malawi's, they are generally kept at a ph of 8 or higher. however that's not my field of expertise so double check it with the people in the african cichlid section.

if that's the ph then yes you can use the existing water..... but there's not really any reason why you should. you should only transfer things between tanks when it's strictly nescessary, there could be all sorts of nasties or diseases you don't yet know about in your malawi tank, the more stuff you transfer across the more chance there is of you transferring something you really don't want to! the filter there is a valid reason to do it, the water there isn't so don't risk it.
also when you start afresh with new water you start off with 0 nitrates, as you will very soon learn your oscar is a poop machine, so the filters gonna have to work really hard, and it's gonna pump out loads of nitrates into the water. if you start with existing tank water that already has a nitrate reading of 30ppm (for example) then in just a few days you could find it's getting up to unsafe levels, whereas if you start afresh with clean water then you increase your margin for error while your getting used to the maintenance needed for your oscar.

so basically if you want to transfer the water you can, but i can't see any benefits to doing so, and there's a few drawbacks albeit minor.

yes beware of sharp edges on anything with an oscar, they're really clumsy and will hurt themself on anything! good thing is they're also very hardy and it shouldn't cause them too much bother if they do, you'll just need to treat with melafix for any nasty wounds to help them heal. everyone i've heard has said you can't plant an oscar tank, but i have and he's leaving them alone (pics in the link in my sig if your interested). some of them are diggers, somenot so much, so really you can just experiment with whats right for you.

yes rocks from the river should be fine but you should boil them first. it also depends what sort of rocks they are as some will leach things into the water, so by all means go hunting, but do a little research before you put it into your tank. there's a good pinned topic around somewhere with details of what rocks are/aren't suitable for your tank.

sand, cichlids prefer it on the whole, they like to dig and sift it through they're gills.

 

[Les Isaacs]

Thanks for this info. I have just checked, and yes - the pH in the malawi tank could do with being a bit higher: so I've done the necessary, and now have a pH of 8. For this reason, as well as the others you have given, I will not be using any malawi water for the new tank.

One minor question: you may recall that I now have an internal fluval 4+ and an external fluval 303 running on my malawi tank (in addition to the two fluval 3+ filters already there), in order to get some bacteria going for when I use those 2 filters in the new oscar tank. I know (I think!!) that "you can never have too much filtration" (especially when an oscar is involved), but realistically should the 4+ and the 303 be perfectly sufficient for the one oscar, one catfish and one plec in a 60 x 18 x 24 inch tank? I do in fact have a 'spare' fluval 3+, and was wondering about putting that in the new oscar tank as well (pre-matured in the malawi tank first): would this be a good idea?

Finally (for now!), regarding stones etc., is it OK to test items simply by putting them (after scrubbing and boiling) into the tank before any fish, then - say after 24 hours - testing the water for ... what (and how)? Ideally I would obviously like to test and decide on stones etc before the fish go in: is this feasible?

I think there should be a radio version of this forum - it would be far more interesting than Gardeners' Question Time!!

Thanks again for the help.
Les

 

[Miss Wiggle]

if you have a 'spare' filter then put it on.

really with such big poop machine's as oscars and plecs you should give it all you've got. I have a tank with an O and a plec, they're not fully grown yet but getting there. I have a bigger external fluval to yours, a comparable rena and 2 internal filters just for good measure.

and i still have to work hard to keep on top of water quality. be under no illusions as to the mess these fish can make!!

put every filter you have around on the oscar tank, and be prepapred to go buy some more!

not sure about the rocks to be perfectly honest, there's something called the vinegar test, not sure how it works or what it's testing for though.

here's the pinned topic on them, hopefully that will give you some help.

 

[Les Isaacs]

Thanks once again for all this info.: how could anyone ever contemplate setting up any tank - let alone a big oscar tank - without all this info.?

I have now read and received a great deal of info. to help me 'get this right', and have more-or-less formulated the following plan:

This is where I'm at now:
I have a 60 x 15 x 18 inch tank (currently empty, but intended for an oscar a plec and a catfish). plus a 48 x 12 x 12 inch tank (with 14 malawis and a 6 inch plec). The filters intended for the bigger tank (external fluval 303 and internal fluval 4+) are now in the smaller tank, maturing their media - they've been there for 1 day so far.

This is what I hope to do:
In 9 days time (i.e. 10 days after putting the fluval 303 and the 4+ into the malawi tank), I will fill up the bigger tank with tapwater, treat it with anti-chlorination agent (TetraAqua 'AquaSafe'), add the fluval 303 and the 4+ from the malawi tank, and add an oscar, plec and catfish ... all on the same day!! Each day thereafter I will test the big tank water for amonia and nitrite. If either is high I will immediately do a 40% water change (adding dechlorinated tap water). I will continue to do this until the amonia and nitrite levels have been OK for 7 consecutive days, after which I will reduce the frequency of these water tests to weekly, and also at this point I will move onto weekly 25% water changes - irrespective of amonia and nitrite levels.

Does this sound like the right way to proceed? What have I missed? - there's bound to be something!!

Thanks again for any advice etc.
Les

 

[Miss Wiggle]

sounds about right to me.

just clarify one point, if you get an ammonia or nitrite reading, yes you should do a 40% change, you say you'd do one every day for 7 days afterwards. this may or may not be nescessary. I'd do a 40% change at the first sign of either, test daily and every day from then on do a 20% change until they both reach 0. but once they hit 0 you don't need to carry on doing water changes until your 7 days is up. keep testing the water for a few days afterwards by all means to make sure they don't creep up again, but if they're fine don't keep doing changes.

you may also find as the fish grow up you'll need to increase the weekly water changes to 30/40%.

have you had sand in a tank before? do you know how to maintain it as it's a little different to gravel.

 

[Les Isaacs]

I'm glad I'm not far off with my plan - I take on board what you say about subsequent water changes.
I knew there'd be something else though! What is it I need to know about having sand instead of gravel?
Thanks once again.
Les

 

[ox5477]

I'm glad I'm not far off with my plan - I take on board what you say about subsequent water changes.
I knew there'd be something else though! What is it I need to know about having sand instead of gravel?
Thanks once again.
Les

Sand can get sucked up by a regular python so you have to take off the large plastic end and use just the tube. This will create a larger suction an allow to 'hover' over the surface of the sand. The poop and waste is lighter then the sand so it should get sucked up with most of the sand staying put. You will suck up some but thats ok, won't hurt your drain.

Also though, once you've gone over the surface and got all the waste you can see, turn off the python and run your fingers through the sand. This will release any pockets of anarobic gas that has formed. Note for this too I guess, don't put more than 1/4" to 1/2" of sand in your tank if there will be no plants**. A thicker carpet then this will cause anarobic bacteria to set-up house and produce harmful gases that if let alone to build can seriously hurt your fish. But anyways, after you stir up the sand a bit, somemore waste will prob land on the surface of the sand and just go back and syphon up tht waste and finish your water change.

And there you have it, clean sand

**If you plan on having plants, which may not be the best idea with Oscars, but like Miss Wiggle said, her's doesn't bother the plants, but anyways, with plants; the roots will help control anarobic gases as their roots will use the gases formed as part of its food source. So you won't have to worry so much about the depth of your sand in a planted tank.

 

[Miss Wiggle]

what he said