Tropical Fish Forum

Think Fish Tropical Fish Forum => Fish Community Creator => Topic started by: ledbelly on February 13, 2018, 11:37:15 PM

Title: Are my fish stock levels too high?
Post by: ledbelly on February 13, 2018, 11:37:15 PM
Hi, my first post.

I have used this site to help stock my fish tank. I have a 64 litre tank with a fluval 206 external filter and a bit of a newbie.

We have 6 cardinal tetra, 3 galaxy rasbora, 4 embers tetra, 3 threadfin rainbows, 5 male guppies, 4 bronze corys, 2 blue rams and 2 dwarf gouramis. Tanks been going 6 months and we have gradually added fish. Plant wise I would say medium, but they are growing fast with healthy new shoots.

I know some of the fish need more numbers for shoaling but we lost some embers and rasboras and will phase them out.

We do a 20% water change each week.

Fish are all quite active and feed well. Feeding is once a day The dwarf gouramis however have started to look a bit lethargic and one has developed pin holes in its fin.

Should we do more water changes to twice a week or maybe every other day at 10%?
Title: Re: Are my fish stock levels too high?
Post by: Matt on February 14, 2018, 06:54:39 AM
Hi there and welcome to the forum.  :wave:

Unfortunately, I would suggest you tank is possibly overstocked. I have input your stocking and used the oversized internal filter option and you are 122% stocked. Of course if you used external filter as an option this number will come down... I wouldnt use this option personally however as I don't think it provides realistic stocking capacities (others have agreed with this point in the past too). The filter is an external and is oversized for the tank though so theoretically you may be ok, in terms of having enough bactrria to support the volume of fish...

What are your water test results? You should look to test for ammonia and nitrate. Ammonia should be zero if your filter has enough bacteria to cope with the volume of fish. Nitrate will show how often and how much you should be doing water changes. You should look to keep this figure at the level of tap water plus 20mg/l through water changes. With frequent testing you can determine the volume and frequency of changes required. I would suggest doing x2 30% water changes each week might be about right so I would up this straight away.  Improving the water quality should help your gourami too.

The other important things to note is that whilst I know you are phasing out the smaller fish, which would bring your stocking to a more realistic level, you have fish suited to very different water parameters in one tank. The guppies need hard water and the rams soft water.  I would suggest looking up your water hardness on your water companies website, post the number and units they give for hardness and we will convert it into fish keeping language so you can work out which fish are suited to your water.  You can then consider which species to keep long term.  Keeping fish in water of a hardness they are not suited too will lead to organ failure overtime as their bodies struggle to cope with the unnatural environment in which they are living.
Title: Re: Are my fish stock levels too high?
Post by: Sue on February 14, 2018, 09:43:56 AM
To be honest, the idea that having more filtration means you can have more fish is now outdated. As long as a tank can process all the ammonia made by the fish in there it doesn't make any difference how much filtration a tank has, the amount of fish a tank can hold remains the same. All greater filtration does is move the water round faster.

The recommended water change regime is 50% a week - though Matt's 30% twice a week amounts to the same.



The dwarf gouramis - how long have you had them, and are there any other symptoms besides lethargy and pinholes in the fins? The reason I'm asking is because there is a risk they have dwarf gourami iridovirus. This is an incurable disease that an awful lot of dwarf gourami bred in the far east are already infected with by the time they get to the shop. Other symptoms of this disease include darkening in colour, laying on the side on the bottom of the tank and sometimes bloating. Keep an eye on these fish; if they do appear to have DGIV, I'm afraid there is nothing that can be done.
One thing I do need to check, which may sound like a silly question - are the gouramis a male and a female or 2 males?
Title: Re: Are my fish stock levels too high?
Post by: Littlefish on February 14, 2018, 12:45:37 PM
These are also useful links for species information and community compatibility when setting up a tank:-
http://www.seriouslyfish.com/
http://aqadvisor.com/
Title: Re: Are my fish stock levels too high?
Post by: ledbelly on February 14, 2018, 11:19:20 PM
Cheers for you replies, much appreciated.

Matt...my water is classed as  "slightly hard" and the numbers are 9.66. I havent got a test kit but I am going to order one. We did have our water tested a few weeks ago at our LFS and got told no problems. No one has mentioned in the LFS about water hardiness and the fish even though we asked a few basic questions like "will these be okay with these fish" when we bought them.

Sue...the gouramis are 3 months old and both male. They were purchased from the LFS from the separate tanks. Since doing some further research I have read that the males can be territorial and if you do buy 2 males they should be from the same tank. There has been a change in colour and that they look a bit darker on the silver coloured parts and have lost some sheen and depth of colour.

Food wise, the staple is Tetra colour with dried bloodworm and tubifex about once a week.

Title: Re: Are my fish stock levels too high?
Post by: Matt on February 15, 2018, 07:14:38 AM
Annoyingly LFS advice often needs to be taken with a pinch of salt... more interested in sales than fish health very often.  If you can find out the units of the hardness measure I'll convert them into something you can use of the websites Littlefish provided to work out which fish suit your water hardness.
Title: Re: Are my fish stock levels too high?
Post by: Sue on February 15, 2018, 09:43:10 AM
Male gouramis of the more aggressive species, which includes dwarfs, should never be kept together in small tanks. It may be possible in very large tanks with dense, tall decor to break up line of sight and form boundaries. As you  are aware they are territorial and one of them will bully the other, sometimes with one killing the other, or the bullied fish dying of stress related disease. I would go as far as to say that the one with pinholes in his fins is being bullied by the other. You need to rehome one of them asap.
Male dwarf gouramis have also been known to kill females if the male wanted to spawn and she didn't. It is for this reason that if females are wanted, there should be two of them with one male.

There are a lot of websites that are written by people who just keep fish without knowing much about them. Just about the best site is Seriously Fish because that is written by biologists and ichthyologists. This is a quote from Seriously Fish's page on dwarf gouramis http://www.seriouslyfish.com/species/trichogaster-lalius/ (my red highlighting)
Quote
It’s generally not a good idea to keep a group of dwarf gouramis together and the species is usually sold in sexed pairs. We’ve noticed an alarming tendency towards tanks containing solely males in the trade during recent years, and must stress that buying two males is a recipe for disaster unless you have a very large tank. Buying a male and female pair is by far the best way to keep this species. Even then problems can arise as males can be very hard on females on occasion.





A tip, in case you are not already doing it - dried bloodworm and tubifex are better if they are rehydrated before putting them in the tank. If they are put in the tank straight from the pack there is a risk that they will be eaten before they have absorbed water and could rehydrate and swell up in a fish's stomach.
Title: Re: Are my fish stock levels too high?
Post by: ledbelly on February 15, 2018, 12:54:37 PM
I did my tests and ammomia is 0ppm, Nitrite 0ppm, Nitrate was between 5 to 10 ppm.

Ph was 7.6 and then i did a high end ph and it was 7.4

For water hardness the hardness clarke is 9.66. There are loads of other readings like nitrates which are 2mg a litre.
Title: Re: Are my fish stock levels too high?
Post by: Sue on February 15, 2018, 01:34:41 PM
There are two units used in fish keeping, German degrees which are often abbreviated to dH, and ppm which is the same as mg/l calcium carbonate. Fish profiles use either dH or ppm.

9.66 deg Clark converts to 7.7 dH and 138 ppm.
Title: Re: Are my fish stock levels too high?
Post by: ledbelly on February 15, 2018, 11:46:42 PM
Thanks for all the advice, its greatly appreciated. I like having my own test kit and went for the more expensive one rather than the strips.

I know what to look for in the future, where to research and hopefully have happier fish!

Luckily I have found someone at work who can accomodate one of the dwarf gouramis. Fingers crossed the other one improves.

Title: Re: Are my fish stock levels too high?
Post by: Matt on February 16, 2018, 07:57:56 AM
If you now use the seriously fish website and the hardness figure Sue has given below you will be able to see if your fish are suited to your water or not.