Tropical Fish Forum
Tropical Fish Keeping Help and Advice => Fishtank Filtration and Cycling => Topic started by: water watcher on April 19, 2013, 05:24:44 PM
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Hi all,
i am currently fishless cycling a 78 litre tank which i hope to use for a small community tank of danios, tetras, possibly cherry barbs and hopefully some corys.
The water has been in the tank for a few days now and the tests are as follows:
GH - 180 or above definitely as dark blue as the strip goes.
KH - is 120
PH is 7
Do i need to have any concerns about the hardness or stability of my water?
Thanks
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Your GH is ~10 German degrees and your KH is between 6 and 7 German degrees (assuming the readings are accurate; strips can be a bit off). You should be fine, but can I suggest that when you get to the stage where the nitrite eaters are growing and nitrate is being made you keep an eye on your pH. I had a fright this morning with my fishless cycle suffering a pH crash because my KH is about half yours and I hadn't been checking the pH like I should have done :-[ I do know better, I just didn't follow my own advice ;D
The pH should be fine too so long as it doesn't drop below 6.5. Although the filter bacteria prefer a higher pH, they should grow fine at 7.
I notice you give the readings from strips - do have an ammonia tester? Most strips don't have them.
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Yes, i have an API test kit, just using strips at this stage of the cycle.
I think i'm right in saying the higher the GH/KH the more stable the PH is so hopefully i won't have any major variations, but i will keep an eye.
Not really getting much readings on nitrites and nitrates yet. I'm using Kleen Off to introduce ammonia.
Plus i have just added in some bog and driftwood which may alter PH. But that is the beauty of fishless cycling you can play around and all you lose is time.
Cheers
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Yes, it's not as if you can kill any fish with fishless. I'm using Kleen Off as well, but take no notice of the amounts I'm adding in my fishless cycle thread. I got the bottle years ago to keep the filter alive between bettas and some ammonia has evaporated.
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O.K I'm going right out on a limb here but am I right in thinking "water watcher's" ph is less likely to drop as her hardness is high? Is it just the carbonate hardness that helps stabilize the ph or the general hardness too?
I am interested in finding out and understanding more about aquarium water quality as I am close to getting my Discus. :)
My readings are 0 for ammonia, nitrites and nitrates. My ph is a little high (7.6) but I'm going to do a large RO water change this week so that should help. The shop wrote down that my carbonate hardness was 17.9 but when I questioned this they said it only took 1 drop and that is absolutely fine.
I must get bottles to test carbonate and general hardness, I have ammonia, nitrite, nitrate and low and high ph. I'll also invest in a tds reader.
Can anyone recommend a book that explains all this in layman's terms?
Stuart.
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O.K I'm going right out on a limb here but am I right in thinking "water watcher's" ph is less likely to drop as her hardness is high? Is it just the carbonate hardness that helps stabilize the ph or the general hardness too?
I am interested in finding out and understanding more about aquarium water quality as I am close to getting my Discus. :)
My readings are 0 for ammonia, nitrites and nitrates. My ph is a little high (7.6) but I'm going to do a large RO water change this week so that should help. The shop wrote down that my carbonate hardness was 17.9 but when I questioned this they said it only took 1 drop and that is absolutely fine.
I must get bottles to test carbonate and general hardness, I have ammonia, nitrite, nitrate and low and high ph. I'll also invest in a tds reader.
Can anyone recommend a book that explains all this in layman's terms?
Stuart.
The Carbonate hardness buffers pH, the general hardness is the sum total of your dissolved solids, including Carbonates.
There's something fishy going on if you have zero nitrates, it sounds like your tank isn't cycled at all.
If your Carbonate hardness is 17.9 (1 drop) that means it's 17.9ppm and 1o of hardness - which is basically nothing and no protection at all against a sudden pH drop. Having a pH of 7.6 is very unusual if your KH is 1o.
I'm totally confused as to how you have readings like this and as Discus are tricky fish to keep (and expensive to buy) I can only suggest you don't get them until all this is cleared up, especially as you say you want to understand about water quality, which is excellent news. However; you really need to have this well understood before getting Discus.
Don't bother with a TDS meter, but get the other kits and test your water, then lets us know the results. It's a good idea to get the KH and GH kit as you intend to futz around with RO water.
What size tank do you have and are you brand new to fish-keeping? We'll do all we can to help you but we need to clear some things up first before you get fish.... please.
Good start here (http://www.thinkfish.co.uk/article/water-quality-and-testing-for-your-fishtank.html).
Also useful here (http://www.thinkfish.co.uk/article/testing-for-ph-and-hardness-in-an-aquarium.html).
Hope this helps.
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Stuart,
As an afterthought, as it's now the following morning, I see you live in Bucks. So do I, near Aylesbury, so I would think that your tap water is very similar to mine.
My parameters are (after standing for 24hrs): pH 7.6; GH 16o(296ppm); KH 12o(215ppm)
It's a chalky (Calcium Carbonate) area around here so the Carbonate hardness will always be elevated, although it has to be less than the GH.
I really don't see how your LFS could test the KH to 17.9ppm or 1o. If they also tested for Ammonia, Nitrite and Nitrate I'd be worried about the accuracy of those readings, too.
It's definitely worth getting the test kits and doing your own testing.
I use RO water to bring the hardness down to 12o (which gives me a KH of 9o) - but it has no effect on the pH because the water is so well buffered, so if you're intending to use the RO to bring the pH down to (say) 7 then it ain't gonna happen. You'll have to buy all RO water then 'build your own' water using the proper mix of 'salts' to get a low pH water that's well enough buffered not to suffer pH crashes. Either that or filter your water through peat. There're plenty of tutorials on the net on how to filter through peat - (though personally I would never use peat 'cos of environmental considerations).
These are just some thoughts that I think need thinking about before you get your fish. I'm really not trying to be negative in any way and I may have got the wrong end of the stick and you're totally sorted and prepared..... but I have a feeling that you're not there yet. (and I really wouldn't have spent 20mins typing all this out if I wasn't concerned - I'm still a two-fingered keyboard pecker :) )
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Sorry, perhaps I should have been clearer.
I have been keeping fish in my 4', 180 litre tank, for a couple of years now.
The filter media is well cycled, although I recently removed all the water to clean the tank and paint the background. To spread the cost I refilled the tank with treated tap water and have been doing 35 litre water changes with RO every week or so since.
When I first went to get the water results the lady said the carbonate hardness was 1 drop. ???I looked confused so she then explained that it was fine. After I left the shop I noticed she had written 17.9 for carbonate hardness.
I went back yesterday to get some more RO and asked the guy, that was near the woman when she did the teat, about the 17.9. He also looked confused and said that seems high! He assured me that it only took 1 drop which was fine for Discus.
The ammonia and nitrites were where I expected them to be. I was pleased with the nitrates but not completely surprised, as I recently brought a (chinese takeaway sized) plastic tub with floating plants in. Those dozen or so plants have now spread to nearly half my tank so they have obviously "eaten" all my nitrates.
My tank has a sand substrate, no rocks or stones which I believe would raise ph in a tank. But plenty of wood which I believe should lower ph, and floating plants.
So, is this right? The general hardness includes the carbonate hardness, but there are seperate tests to measure the carbonate hardness because ultimately it is the carbonate hardness that effects the stability of the ph?
Thanks for your comments ColinB. I can understand you thinking I am a complete newbie as I don't get on here as much as I did the old site. So little infact that Sue may have even forgotten about me (and boy did I used to hassle her with endless questions) ;D
Stuart.
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So, is this right? The general hardness includes the carbonate hardness, but there are seperate tests to measure the carbonate hardness because ultimately it is the carbonate hardness that effects the stability of the ph?
Thanks for your comments ColinB. I can understand you thinking I am a complete newbie as I don't get on here as much as I did the old site. So little infact that Sue may have even forgotten about me (and boy did I used to hassle her with endless questions) ;D
Stuart.
Ah - thanks for the clarification.
Yep, GH includes KH, and it's KH that acts as the buffer and stops the pH dropping.
I've got one of these:
(https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcQp1-oEc7g7LeNlBsJU9Y1zc4zLYMqxS-zwKRABjvUfJN5dedEN)
You have to read the small print for how to convert ppm to deg. very carefully as it's different for the two tests.
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Hi Stuart,
I don't really have anything to help you as regards your question about hardness; Maybe Sue can help. However, I would advise you to invest in your own hardness test kit and, from Colin's comments, learn how to use it.
Fiddling with hardness can be like pushing a stone uphill, but you seem to have the details sorted. Relying on your lfs for testing when they are plainly out of their depth seems somewhat risky to me.
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Something I only learned when my son worked for the water testing company:
GH is a measure of divalent cations, that's all. As far as most natural sources of water are concerned, that means calcium and magnesium, the most common divalent cations. GH does not measure monovalent cations like sodium and potassium, or anions like chloride or nitrate.
KH is a measure of how much acid is needed to drop the pH to a certain value. In natural water supplies this is virtually the same as measuring the amount of carbonate and bicarbonate in the water.
I always misunderstood GH. I thought it was a measure of everything dissolved in the water, including carbonate, but it isn't. This is why it's possible to have high KH and low GH. It's total dissolved solids (TDS) that measures everything.
But generally speaking, if you have hard water (high GH) you will also have have high-ish KH.
Sorry, bit of a rushed answer, I'm trying to get through all the posts while I've been away.
Edit to add:
I've just done my regular tests on my cycling tank, and did GH and KH as well. If you've read my cycling thread recently, you'll know I had a pH crash last week. When I set the tank up 6 weeks ago, my GH was 7o German and my KH was 3o German. (Multiply both by 17.9 to get ppm). The pH crahed because my KH is so low. I added bicarbonate of soda (chemical name sodium hydrogen carbonate) to raise the KH and prevent any further crashes during cycling.
The GH test I've just done gave 6 to 7 (by which I mean the colour changed slightly at the 6th drop and had changed completely with the 7th. So adding the bicarb did nothing for my GH. The only cation in bicarb is the monovalent sodium - and adding a lot of this has not affected the GH reading at all.
The KH test gave a reading of 11 to 12. This test changes from blue to yellow at the end point, it is much easier to see than the GH colour change. At 10 drops it was deep blue. At 11 drops it was green and at 12 drops it was bright yellow. So it was beginning to change at 11 but was complete at 12 so I'm calling that 11 to 12.
My cycling tank therefore has a KH almost double the GH which means the GH test cannot include KH, exactly what my son told me.
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I always misunderstood GH. I thought it was a measure of everything dissolved in the water, including carbonate, but it isn't. This is why it's possible to have high KH and low GH. It's total dissolved solids (TDS) that measures everything.
But generally speaking, if you have hard water (high GH) you will also have have high-ish KH.
That's exactly what I thought too. All the reading I'd done told me this.... until late last night on this (http://www.wetwebmedia.com/index.html) web site. I was looking to see about keeping a single Honey Gourami in my tank and I really rate this site as a source of reliable information, but it takes ages to wade through and find.
I found this info:
Ah now, aquarium salt -- sodium chloride -- will neither raise nor stabilise GH or KH. General hardness is primarily magnesium and calcium salts, while carbonate hardness is primarily carbonate and bicarbonate salts. Sodium chloride falls into neither category.
As Sue's son says, Magnesium and Calcium are divalent positive ions (2+ elecrical charge); Mg2+ and Ca2+ for GH
...and Carbonate and Bicarbonate are negatively charged ions; CO32- and (HCO3)- for KH
As Sue says, GH and KH are generally found together. Here in the south of England it's very chalky and a hard water area. Chalk is Calcium Carbonate; CaCO3, so when this dissolves in water it splits into Ca2+ which will raise your GH, and CO32- which will raise your KH.
When Sue added BiCarbonate of Soda (Sodium Hydrogen Carbonate; NaHCO3) to her water, this split into Sodium ions, monovalent positive, Na+, so this didn't add to the GH; and BiCarbonate ions, (HCO3)-, which did add to the KH.
However, the added Na+ does add to the Total Dissolved Solids, TDS, and this will affect the osmotic pressure on your fish (again from the linked site). This is why water softeners are not a source of soft water suitable for fish. Water softeners (either cartridge kitchen ones or plumbed in salt ones) replace the Ca2+ with Na+, so the water isn't classed as 'hard' and doesn't fur-up your pipes, but it doesn't change the TDS or the ammount of osmotic pressure on your fish. Only Reverse Osmosis (RO) water physically removes TDS from your water.
All this is a way of saying..... sorry for the bum info Steve :-[, but I've learnt quite a bit from my research and combining it with Sue's post and I hope it's been helpful.
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Good summary Colin, thank you. My post was a bit garbled as I was rushing ;D