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Confused on KH GH etc and keeping Chocolates

jayp

Member
Joined
20 Mar 2010
Messages
59
Location
Cheshire
HI, Ive set up a new tank a month ago , ive kept Chocolates before with some success and some fails

Tank has been set up using old mud/dirt/planting medium with a sand capping
Also kept old filter going and put in new tank

Water is clean rain water which ive used for years

So its a no fish cycle of new tank , now all scaped and ready but water not ready !
25% water changes every 4 days

LFS tested water for me today

Ammonia 0.25
Nitrite 0
Nitrate 40
PH 6.4
GH 3
KH 0

LFS suggestions before adding fish
Continue with water changes and re-test in a week to see if Nitrates and ammonis dropped

Add buffering to increase KH

I'm not sure about the buffering chemical ....ive kept Discus using the same water and they were fine for years

Ive kept the \chocolates for over 12 months until I added another 3 fish ....they all died. So I tried a fresh batch and they all died

Hence complete revamp, change of tank to a better size 60x45x30

Can anyone advise as my Chemistry is complete rubbish and I'm just not sure what to do that will be best for the fish ...its a nicely planted scape but low-tech

Jan x
 
tank 1.JPG
tank2.JPG
 
Are adding ammonia to cycle? Adding mature filter medium is great, but the bacteria need food to survive so either fish waste (as you've added fish) or some other source of ammonia in the mean time.

Be worth checking the rainwater before you add to see what that reads too.

It's my understanding KH helps stabilise your PH, buffers it, so it's harder for it to swing about suddenly. There is discus remineralisers available you could consider to add a bit in - though check whether they actually add KH. I use Tropic Marin for my RO - I've heard people use a mix of that and Tropic Discus for a particularly low GH and low KH. I just use a slightly lower dose of the Marin - for soft water but not discus levels of soft.

Things like substrate and what you add - wood, rocks etc. can all effect the buffering so that may explain why what worked on one tank doesn't on another.
 
LFS tested water for me today
Sadly collecting water and bringing it to the LFS will probably create differences in the true watervalues already.
Choclates come from very soft water with low pH's (http://www.seriouslyfish.com/species/sphaerichthys-osphromenoides/) So just using rainwater should be sufficient (as long as it isn't polluted).
To speed up the tank you could add some easy pondplants to increase plant mass to be able to have them use ammonia and nitrites faster.

I am afraid there are a lot of choclate gouramis who don't handle the fishtrade very well, they are sensitive and need carefull handling, if not you'll end up with diseased fish. Buying these can be bad.
 
Thanks for replies ,
Tam , LFS gave same advice which is good , they suggested the Tropic Marine and just use enough to raise KH to 3 or 4 , and retest . I have a few snails so they will need some mineral content I think . I will also test rainwater I'm using ...good idea as although collected from a clean roof and covered it would be good to know the readings

Edvet, yes they are especially difficult to get through the trade , its such a shame and this will be my last attempt at keeping them, they will be the only fish in the tank in a group of 6 . I suppose I was so delighted when I kept 4 successfully I wanted a last go. I know the set up will be good for them once ive cycled properly and the regime of 25% water changes once a week and only feeding live food works well. Nothing else really floats my boat apart from Liqourice Gourami and no-one ever has any for sale
 
I find a TDS pen quite handy for mixing, once you get the water to water you want (full dose of Tropic Re-Min gives you around 7GH 4KH so you probably want a bit under) then you can measure the TDS instantly with the pen and mix to that rather than having to test/estimate how much to put it.
 
I keep my softwater fish in pure RO diluted with about 30% tapwater, 50-80 microsiemens.

I've started experimenting with that for one of our bigger tanks - our tap water is GH19.
 
Ive checked Rainwater today , as yes, no use doing water changes if don't know what you are changing it with .

Came back as 0 for everything except PH was 5.9 % so a bit lower than my tank
Ammonia 0
Nitrite 0
Nitrate 0
PH 5.9
GH 0
KH 0

On that basis have done another 25% water change and added minerals for full tank
Have also added a job lot of frogbit

Will change another 25% tomorrow
 
Hi all,
I'd add some leaf litter, we don't know quite why it works but it is <"definitely beneficial".>
Came back as 0 for everything except PH was 5.9 % so a bit lower than my tank
If you don't have any carbonate buffering (our rain-water picks up some from limestone dust) then the dissolved CO2 will lower the pH~pH5.9.
Are adding ammonia to cycle? Adding mature filter medium is great, but the bacteria need food to survive so either fish waste (as you've added fish) or some other source of ammonia in the mean time.
My LFS says.......Add buffering to increase KH
It's my understanding KH helps stabilise your PH, buffers it, so it's harder for it to swing about suddenly.
Their is a certain kernel of truth in these, but they aren't really relevant to keeping black water fish in planted tanks.

When working out the capacity of microbial nitrification oxygen availability is the prime metric, which is why scientists refer to the bioload using Biochemical Oxygen Demand (BOD). Low ammonia loadings create a diverse microbial fauna that can respond changes in ammonia level. In ecology diversity brings stability. All the recent scientific research points to aquarium nitrification being overwhelmingly carried out by Archaea and COMAMMOX <"Nitrospira">, and they don't have the same requirements for ammonia or carbonate hardness that the bacteria which carry out ammonia oxidation in sewage treatment etc do, <"Freshwater Recirculating Aquaculture System Operations Drive Biofilter Bacterial Community Shifts around a Stable Nitrifying Consortium of Ammonia-Oxidizing Archaea and Comammox Nitrospira"> & <"Kinetic analysis of a complete nitrifier reveals an oligotrophic lifestyle">.

It is the same with carbonate hardness, very soft water doesn't have any, and the pH will be unstable. If you have fluctuating pH in a Tanganyikan cichlid tanks it is a problem (because the water should be so heavily carbonate buffered that it needs huge changes in water chemistry to effect pH), isn't a problem for black water fish, any addition of acids (like the CO2 in the rain-water) or bases (including dissolved oxygen) will cause changes in pH.

cheers Darrel
 
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Blimey Darrel ....that's way over my head . So are you saying my KH of 0 and a fluctuating PH wont matter to keeping Chocolates as they are used t such PH changes ? I do find all the info a bit confusing.
I kept Marines for 5 years using rainwater ...thought my rainwater was as close to RO as necessary. I changed water often and didn't have any water issues ...the outbreak of flatworm made me give up .

Thanks for he info ...will have a read and hop e something sinks in
 
they are used t such PH changes
They are, It's called weak acid reactions, these wont hurt soft water fish. (like you can drink a glas of cola (pH =2.5!!) but not a glass of batery acid (at pH 1). When i did CO2 on my big tank i had a pH drop of almost 2 full, points every day, fish never cared.
 
Thank you ...that would explain why I could breed Rams in just rainwater . I think maybe what I will do is use the buffer seeing as ive bought it now ...get my water to the same as LFS which is similar to mine ...we have very soft tap water round here, then slowly stop mithering with buffering and just keep water changing on a regular basis . Start adding plant ferts to keep the plants looking good . Just hope the chocos are not too stressed by transport etc and are in decent condition when I get them .
 
Update ....gave up on the Chocolates , didn't get any in the end , felt too bad about them dying just because I wanted them ! So change of plan ...scape is doing fab ,Buce flowering , ordered more Buce , no algae, happy days
Had to get decent cover so had glass cut to size around light clip-ons and cables ...lordy loo la cost me £50

Decided on Killi's got 2 pairs of Striatum which have to say are pretty stunning , colours rival anything ive kept before , already mating daily
 
When i did CO2 on my big tank i had a pH drop of almost 2 full, points every day, fish never cared.

That's because CO2 as an acid does not affect the KH. Its the KH drop one doesn't want as it comes with a multitude of chemical processes affecting the fish.

I am not sure what type of nitrifying bacteria/archaea is in my water but I know it uses KH, the one we test for, during nitrification. If you set up a tank and don't do water changes, you'll see the KH drop in time steadily. And this type of drop is certainly something you don't want. The Ph may/will stay the same as long as there's some KH reading but the fish are affected nevertheless, not just by the drop of course but by the "causation". My point is, KH is used up in nitrification.

Their is a certain kernel of truth in these, but they aren't really relevant to keeping black water fish in planted tanks

Perhaps its true only for certain types wild caught black water fish. For the rest some KH reading would be better to keep things stable long term. With a KH of 2 for example and a very low TDS one still has good soft water environment to keep black water fish. There's no need for extremes and the Ph is not the one that matters. In nature black water fish live in very clean water, void of minerals. The Ph is an irrelevant measure but its reading is affected by certain minerals, hence just an indicator that one's water is not so "pure" .

I've read a lot about clown loaches, which are considered blackwater fish. I can't argue statistics on a large scale but plenty of information of unsuccessful stories pointing out that "home-made" acidic water is actually detrimental to them. All my saved images are gone, otherwise I would have shown what "home-made" black water can do to "black water" fish. They do better in soft but "stable" water. And if that is not an option, they'll do better in harder but stable water, than in wildly swinging acidic water, void of buffering capacity with ph ranging from perhaps even 3 to 6. I am not a scientist and I can't tell you why that is. My guess is that non-buffered fish tank is totally not the same as black water non-buffered lake or river. There are different factors and chemical reactions at play we can't reproduce in fish tanks.
 
I keep fish in almost pure RO water, 40-50 microsiemens. Not sure how much KH is in there.

I keep my softwater fish in pure RO diluted with about 30% tapwater, 50-80 microsiemens.

Roughly 30% of whatever your tap water is? Surely there's some KH if you're mixing with tap.
 
Hi all,
My guess is that non-buffered fish tank is totally not the same as black water non-buffered lake or river. There are different factors and chemical reactions at play we can't reproduce in fish tanks.
The scientific research in this area is very strongly suggestive that it is the humic and fulvic compounds from the leaf litter that have <"important health promoting effects for the fish">. If that link isn't available the original reference is <"Steinberg, C. 2003. Ecology of Humic Substances in Freshwaters: Determinants from Geochemistry to Ecological Niches">.
And if that is not an option, they'll do better in harder but stable water, than in wildly swinging acidic water, void of buffering capacity with ph ranging from perhaps even 3 to 6.
You are right , the pH of this type of water is inherently unstable, as soon as you buffer it you have a very different type of water. The fish have evolved in water where pH is a movable feast, the problem lies with interpreting pH. A pH of pH3 tells you that you have a 1000 proton donors (acids) for every proton acceptor (base), but it doesn't tell you anything about how many there are, just the ratio. As you move towards pure H2O pH is a fundamentally meaningless measure. We can use conductivity for tell us how many ions we have and once we get below about a fifty microS pH doesn't really help us at all.

There is a more complete discussion in <"Apistogramma forums: pool filter sand vs......."> and linked threads.

cheers Darrel
 
The scientific research in this area is very strongly suggestive that it is the humic and fulvic compounds from the leaf litter that have <"important health promoting effects for the fish">. If that link isn't available the original reference is <"Steinberg, C. 2003. Ecology of Humic Substances in Freshwaters: Determinants from Geochemistry to Ecological Niches">.

From what I know humic and fulvic compounds can act as a buffer in acidic tanks, thus making it less acidic, and have the opposite effect in hard water. So in a way very soft water is still buffered with that difference in a fish tank you don't know how well you've buffered it because you can't measure that type of buffer,....hence not successful for everyone. Plus I think people with black water tanks may be avoiding regular large water changes in order to utilise the life of the humic and fulvic compounds they've added. But if you're starting with water that is somewhat buffered plus keeping the TDS stable via water changes, one has a good starting point. Any drop in Kh and rise in TDS in a non-fertilised tank means pollution. Problems come when one tries to keep a particular Ph value stable. As you've mentioned, whether its stable or fluctuates, is largely irrelevant to water quality.

If one has managed to keep fish happy in completely non-buffered water,good for them. But that's not easily replicated in every fish tank. Take into account long term success as that's when issues arise, in 6 months, a year, slacking on a good few water changes and bang....fish gone...although you're still doing the same thing....
 
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Hi all,
If one has managed to keep fish happy in completely non-buffered water,good for them. But that's not easily replicated in every fish tank.
I definitely agree with that, some carbonate buffering makes tanks easier to manage, this is partially because you get better plant growth.
Plus I think people with black water tanks may be avoiding regular large water changes in order to utilise the life of the humic and fulvic compounds they've added.
Some do large volume water changes, some don't, in either case the tanks tend to be fairly lightly stocked.
So in a way very soft water is still buffered with that difference in a fish tank you don't know how well you've buffered it because you can't measure that type of buffer,....hence not successful for everyone.
The humic compounds are definitely important, you can get an estimate based on tint of the water. The darker the tint is, the more DOC is present. As an aside dKH tests don't actually measure carbonate hardness, they measure all the bases.

It isn't a fish keeping style that every-one is going to be successful with, but a few people can keep and breed black-water fish like Chocolate and Licorice Gourami, Heckel Discus, Dicrossus filamentosus etc.

cheers Darrel
 
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