My water conditions, help, do I need RO or HMA or neither.

Sadly you pay your money you make a choice
Darrel has given good sound scientific based advice.
My system works for me
I just use HMA and RO mixed with almond leaf to make the water acidic.
I add not one item of jollop just natural items and it works for me
A lot of advice is based on the cheap way a lot is based on cutting out some thing.
I believe you can’t reduce any thing by adding anything.
In your position I would drop all the jollop get RO and HMA and use almond leaf to make the water acidic.
What you’re looking for is water that is as near to nature as you can get it.
Jollop aren’t going to do that. Striping the water will allow you to add natural items ie alder cones and Almond leaf to get natural water to a point.
The substrate should buffer the water
So in short
Kh 4 to 6
TDS under 200 is what i aim for
The Ph will sort it self out as will all the other things.

Thanx Bob, will go the RO/HMA way then. Since my tap water is GH5 and KH3, using a RO Unit will not effect this or will it and will Alder cones or Almond leaves increase to be more in the 4-6 range.

TDS of my tap water is only 103, API 6.5 buffer increases this to 243. But I have now stopped using the API buffer and only using Seachem Prime now, just hope I don't get a Ph crash, but monitoring it 3 times daily.

Again I value your advice and thank you for your patience,

Once the water has run through the RO and MHA unit you can add Almon leaf and alder cones to give you a sort of black water.
I would be incline to add some min,s try this I use it when I need to add mins
http://dennerle.com/global/index.php?option=com_content&view=article&id=319:osmose-remineral&catid=51:osmose-wasseraufbereitung&Itemid=94&lang=en

Hi all,
Stuart I'm not being funny, or denigrating other people or other forums, but lots of people are willing to state all sorts of "facts" without any real experience or scientific knowledge to support them. Just ignore what every one else tells you. In fact you can ignore me as well.

Listen to Bob (and thegeeman) they use RO and HMA mixed in the way they describe and they have hundreds of fish and fry, including fish I'd never even heard of.

Now we've got the water results we are really getting somewhere:

"My tap water has the following parameters
Ph 8.40
TDS 103
GH 5dKH (107.4ppm)
KH 3dKH (53.7 ppm)".

Click to expand...

Strange as it may sound, as this starts with pH8.4, this is actually a very good starting point. Your pH8.4 is a very long way from the pH8ish that I get in our infinitely carbonate buffered tap water.

TDS 103 - so about 150 microS, fairly low conductivity. This means that there aren't many salts of any description, and no reservoir of buffering (to go back to the tea cup analogy, there is very little sugar in your tea and it has all dissolved.)

Hardness, dGH 5 and dKH 3 some hardness and buffering, but not too much. Almost perfect except for the pH, but in this case we can be almost certain that the pH relates to a relatively small amount of alkaline (or basic) ions in your water, not a carbonate ion because of the low dKH value, so this is almost certainly the very small amount of the strong alkali "caustic soda" (sodium hydroxide - NaOH) the water company added, specifically to raise the pH and stop the water dissolving lead/copper pipes.

Tank Conditions:
PH 6.64 (held there by 6.5 Buffer, but changing this now to Seachem Prime)
TDS 243
GH 3dKH (53.7ppm)
KH 2dKH (35.8 ppm)

Click to expand...

TDS has gone up to 243, almost certainly because of the buffer, because both dGH and dKH have gone down. The drop in dGH/KH is probably via bio-acidification or the humic acids from Indian almond leaves swapping H+ ions for Ca2+ ions). Because dGH/KH are lower you haven't added any Ca2+ or carbonates, but you have added something that lowers the pH, down to pH 6.6.

To buffer a solution to pH6.5 you would normally use a phosphate buffer utilising the acid/alkali equilibrium between di-sodium hydrogen phosphate (Na2HPO4 - a weak acid) and mono-sodium hydrogen phosphate (NaH2PO4 a weak base), and that would be my guess, that you have been using a phosphate buffer <http://www.aquatics-online.co.uk/catalogue/a-p-i-water-adjusters.asp>.

The good news is you definitely don't need the buffer. The pH of your tap water should reduce naturally as you add weak acids from peat filtration, Indian almond leaves, Alder cones etc. It may need monitoring to stop it declining to too low a pH, you can buffer it back up with some Oyster shell grit or 4dkH solution like the one in Bob's link.

You may not actually need it but the RO unit won't do any harm, the membrane will last a long time and you will have little "waste" water. The same with the HMA filter, it should last a long time because your water is pretty pure all ready, and it will make sure you don't have heavy metal problems.

cheers Darrel

What a perfect reply Darrel, thank you for that.