Tropical Fish Keeping - Aquarium fish care and resources

Tropical Fish Keeping - Aquarium fish care and resources (
-   Beginner Freshwater Aquarium (
-   -   New 35-litre tank cycling and stocking questions (

tanker 03-13-2010 10:24 AM

New 35-litre tank cycling and stocking questions
I have a newly set up 35-litre tank measuring 44cmLx42cmHx27cmW (roughly 9 US gallons, I think - 17.3"x16.5x10.62 inches). The filter has "bio-balls", then a bag of carbon wrapped in filter material, then "bio-rings". I have a 50W heater and a small airstone in there as well.

I have been reading extensively and I've read and been given (by sales staff) so much conflicting information that I just want to scream.

I'd like some advice as to whether I'm doing anything wrong and as to how many fish I can have in the tank after it's finished cycling.

The guy at the aquarium shop sold me 5 platies to cycle the tank with (it sounded like a lot to me after what I'd read, but I assumed that he knew what he was talking about). I've had them a few days. I've been doing 10% partial water changes every other day. I had the water tested at the shop today and was told that it was fine. I bought some testing kits so I can test ammonia and nitrite at home so that I don't have to keep going to the shop. Is this ok so far? Should I do bigger water changes when the ammonia level goes up? Any other advice?

My second question is in relation to stocking levels. I have been reading, using online calculators and asking at the shops and I've read/been told I can have between 2 and 15 platies for this tank and I've also read that platies are too active for so small a tank (after I'd got them, of course).

So, are platies ok in this small a tank, and, if so, how many? Is 5 the limit (hopefully it's not too many)? If I can have more fish, could I have a dwarf gourami or some type of bottom feeder or algae eater, or should I stick with platies?

Thanks for any help.

Byron 03-13-2010 01:43 PM

Welcome to Tropical Fish Keeping. You will find many with sound advice here, unlike (sad to say) some stores people.

I would suggest that a 10g tank is too small for healthy platys. Certainly not five or more. Concerning the cycling, monitor ammonia daily, it will rise above .25 and during that period daily partial water changes will help ease the stress on the fish. The ammonia will begin to drop, and the nitrite will begin to rise; above .25 do daily partial water changes. These changes should be only the water, do not vacuum the substrate where the bacteria will be colonizing. Change 40-50% of the tank volume each time, using a good conditioner. One that detoxifies ammonia and nitrite will be best, like Prime.

Looking to the future and fish, do some research and decide what sort of aquarium you want, and what type of fish. There are different types of fish, obviously with a 10g they will have to be smaller species, but there is a multitude of possibilities. The number of fish will depend upon which species you decide. Having live plants will benefit the fish and maintain better water quality, so that is something else to consider. Your tap water parameters (pH and hardness) are important, because it is easier to find fish that will be OK in your type of water than selecting fish that will not, because adjusting water parameters is often fraught with problems. Several here will be able to offer more suggestions when we know your tap water parameters.


tanker 03-13-2010 08:06 PM

Thanks for the reply.

I went to an actual aquarium shop rather than just an ordinary petstore because I thought that the people there would have the knowledge so that I'd come away with something suitable for my small tank - that's what I asked for. That's it as far as the sort of fish I want. I want fish that'll be "happy" in a small tank, I don't care what they are.

The tap water here is naturally alkaline. It tested at the top of the chart (7point8 - it comes out as a smiley if I type the decimal point). The guy at the aquarium shop sold me some "neutral regulator" which is supposed to bring pH down.

If platies aren't suitable what do I do now? Ask the shop to take them back? Why aren't they suitable when they only grow to 5cm? Would they be suitable in a 75L tank? I could get a bigger tank.....

And so it goes, my endless confusion...:lol:

Byron 03-13-2010 08:31 PM

I would not use chemicals to alter pH, they generally do not work. The pH of your water is being buffered by the hardness (carbonate hardness, KH) and attempts to adjust it with any sort of chemical usually results in fluctuating pH as the water's natural buffers restore it. It is better to know the pH and hardness of your tap water (assuming that is what you will use in your aquarium) and then research fish that do best in those parameters.

Libebearers are well suited to basic/alkaline and harder water. The one drawback is that they produce live young and these will quickly overtake the tank. I'll leave it to those with more livebearer experience to suggest species, but there are some very nice small species if you can get them in Australia. There are also some of the tetras that will do well in your water; check out the Fish Profiles section of this forum, the water parameters are given for the fish species. Some of the Asian fish like danios will also do well in basic water. And there is a beautiful fish called the Celestial Rasbora which is actually a danio, but very small and colourful, and best in basic water.

A larger tank is always a great option:-D, if you have the space and the money, you will have larger and more tanks, believe me. We all start out with that one tank, but most of us don't stay there very long.;-)


Austin 03-13-2010 09:12 PM

I think about 3-4 platies in a 10g tank is about what you should keep. If you're stuck with the 5 it might be ok. 5 is a bit too much fish to cycle the tank if you chose to cycle with fish (not the most humane method, but don't feel bad!).

You should test the water with your own test kit. Buy a liquid test kit - if you can't get one then just change about 50% of the water daily or every other day while it cycles (which will take a few weeks).

7.8 PH should be fine for your platies... i'd return the PH thing. it's a waste of money. you don't need it.

A 75 L tank (I think about 20 gallons, right?) would be perfect for the 5 platies and you could maybe get 1 or 2 more fish depending on what kind.

I wouldn't trust most fish store employees even at aquarium stores, btw (though aquarium stores generally do have more knowledgeable employees). Just a bit of advice....

tanker 03-13-2010 09:28 PM


Ok, I'm going to get another tank. I'd already had my eye on a bigger one and now I've got a good excuse to get it:-)

Maybe I could have guppies in the 10L? They keep the males and females separately, so could I just get all males? How many? Could I get some sort of bottom feeder/suckerfish with guppies?

What other fish would cohabit happily with the platies in the bigger tank? Some sort of bottom feeder? Dwarf gourami? How about the numbers? Would I have room for a small school of tetras as well as the 5 platies (I suppose it depends on the type)? How many? I quite liked the look of the silvertip ones. Would they be suitable? I'll have a look for celestial rasboras. Don't danios need a lot of room even though they are small? I'll have to do more reading, but all suggestions are gratefully received.

What should I do now in relation to cycling the tanks? Should I leave the platies where they are until the small tank is cycled and then move them, or move them to the new tank when I get it and put guppies in the other one? Are guppies suitable for cycling?

Thanks again for the help.

Byron 03-14-2010 03:19 PM

Any fish that is placed in a new tank that has to cycle will be stressed by the cycling. Some tolerate this and survive, some don't. Mollies among the livebearers are very bad for cycling because they are very sensitive to ammonia and seldom make it through the cycle. Platies are closely related, so as you have them, I would monitor the ammonia (think you mentioned a test kit earlier) each day, test at the same time each day to get an accurate indication of any rise in ammonia, and if it is above .25 do a partial water change using a good conditioner like Prime. Prime detoxifies ammonia and nitrite, so it is very good in new tanks, but the detox only lasts about 24 hours so if ammonia or nitrite rises a day or two later, time for another water change. You can change 40-50% of the tank water each time.

The cylce will work its way through in a couple weeks, the period depends upon many things in the tank and water, so it varies.

tanker 03-15-2010 12:09 AM

Thanks. The ammonia has been testing at 0.25, but I've been doing partial water changes anyway. Is this wrong? Should I let the ammonia build up more before doing the water changes? I'd rather keep the fish alive (one's completely disappeared, I hope he isn't dead somewhere....) and minimize any harm to them than have the cycle go quicker, but I need to know if I'm doing it all wrong.

Byron 03-15-2010 01:23 PM


Originally Posted by tanker (Post 344445)
Thanks. The ammonia has been testing at 0.25, but I've been doing partial water changes anyway. Is this wrong? Should I let the ammonia build up more before doing the water changes? I'd rather keep the fish alive (one's completely disappeared, I hope he isn't dead somewhere....) and minimize any harm to them than have the cycle go quicker, but I need to know if I'm doing it all wrong.

Water changes can not hurt, but if you are using a good conditioner that detoxifies ammonia, I would not do daily water changes unless the ammonia rises sharply the day after the last one, or any successive day thereafter. Detoxifiers in water conditioners work by changing ammonia into ammonium which is not toxic, and bacteria still use ammonium or ammonia so no problem there, plus a test kit for ammonia will normally read ammonia and ammonium the same so it will still show "ammonia" even though it may actually be ammonium.

The point in all this is to monitor daily; if you do a water change with an ammonia-detoxifying conditioner today, and the ammonia test reads .25 that is actually ammonium, harmless; it it is still .25 tomorrow, you're OK. If it is .50 tomorrow, or the next day, then do another water change with the conditioner, since the increase in ammonia is probably ammonia and not ammonium. Conditioners that detoxify work for about 24 hours.

If your water in the tank is acidic, pH below 7.0, ammonia again automatically changes to ammonium in acidic water so there would be no concern in this scenario. But in basic/alkaline water, follow as above.

Hope this makes sense and helps.


tanker 03-16-2010 01:03 AM

Thanks. Yes it makes sense.

I've just been using "water ager" which removes chlorine. I'll go to the shop and look for something that neutralizes ammonia as well.

All times are GMT -5. The time now is 10:40 AM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.

For the best viewing experience please update your browser to Google Chrome