tropical fish

[spudo]

what does "GH" mean is fish terms and how important is it for keeping discus fish.
and how can i reduce it or raise it if i need to?

thanks.

[wildwood]

Are you sure you don't mean PH?

Discus fish need water well below 7 (acid) which can be reproduced by putting spagnum moss in the filter.

If you use undergravel filtration you can soak moss in a bucket and use that to refresh 10% of the water every week, depending on the number of fish you have.

There is heaps of info on the Net; google for "discus ph" and you'll get more information than you could hope for.

[hammerman]

Please ignore the above answer. You do not lower the pH by adding moss....you add PEAT !!!

GH stands for General Hardness and is far too complicated for me to sit here and type a long reply out...do a search on the web...lots of articles about.

In order to breed discus (they're not called discus fish !!!!) you will need to find out what water they are being kept in. Some discus will happily breed in hard, alkaline water with a pH of 7.5+ whilst other will only breed with a pH of 6.5.

Apart from peat, by far the best way to soften your water is by using a remerse osmosis unit (RO). This strips tapwater back to it's bare bones and removes 99.9% of everything leaving pure water. However, as it's so pure, it's often better to add 50% tap water with it just to get a few of the minerals back in.

Bogwood, blackwater extract and Indian almond leaves will all produce tannins and turn your water brown, this give the perfect blackwater llook and feel for the fish so think about using those too.

have a look here at a few sites

http://ukaps.org/forum/

http://www.uk-aquarist.com/index.php?&act=idx

http://www.fishforums.net/

[hammerman]

Typo...***Reverse Osmosis***

[spudo]

thanks again hammerman. you have awnsered another one of my questions :D

[Matkop]

Water 'hardness' has two varieties - GH (General or 'permanent' hardness) and KH ('temporary' hardness). As hammerman says, it's a complicated subject, but trying to simplify it: KH is the dissolved minerals that come out when water is boiled (see the scale in your kettle? That's the 'carbonates' (KH) which have come out of the water. The GH stuff is all the other minerals that can't be removed by boiling.

Generally, Discus prefer the GH and KH values to be low (but will tolerate higher levels if they are gradually acclimatised). The major effect of high GH/KH levels for Discus is not on breeding behaviour, but on the fertility of the eggs. High hardness = eggs with "tough" walls which then can't be penetrated by the male's 'milt' (sperm).

Most of the UK's tapwater has quite high GH / KH levels, so my Discus are kept in water from a Reverse Osmosis system which has been conditioned beforehand by adding a carefully measured mix of the "correct" minerals back in - the product I use is "Pro Discus Mineral", but there are others out there such as "RO-Rite". One 'side effect' of low KH is that the pH value of the water can change quite rapidly, and that is VERY stressful for the fish. If you don't really need low KH levels, don't bring them down below 2 degrees of hardness unless you are prepared to watch the pH levels like a hawk!

The bottom line is that if you are not going to breed your Discus, don't worry about getting the GH/KH levels "right" - just keep checking them to ensure they are reasonably consistent!

Good luck!