Something in tank is raising GH. Any ideas?

[mourt]

EDIT: Well, I've just done another round of testing, and actually it seems like something in the TANK is raising GH instead.

I have a planted tank with eco-complete, some rocks and thats about it.

Annoyingly the hard water is from the tap I want to use to fill my discus tank! All the soft water taps are interior so far that I have tested. Does anyone know what could cause this and possibly a means of fixing?

I would have thought all the plumbing in the house would be one and the same, but apparently not.

I bought a an RO unit but the waste water produced is shameful, and I can't bring myself to use the damn thing.

[Hollowman]

Do you have a built in water sofener in the house??

RO units do produce waste water, but you can minimilise it by using a high pressure pump which increases efficiency or you can piggy-back another membrane (or 2) to the system. I have 2 - 100gpd membranes on my system and with the pump I get about a one to one ratio of waste to product. The waste water is collected in a water butt to water the garden.

Here is my RO setup to give you an idea.

http://i248.photobucket.com/albums/gg188/Discusboy123/DSC01286.jpg

[mourt]

Ooh.. Nice.. How incredibly organized, unlike me. It may be a little expensive for me right now, but definitely a consideration for the future.

I have no water softener in the house that I'm aware of. The water in Sydney is meant to be relatively soft all over.

[brad_v]

Does it just need a flush / increased use?

[bartek]

What are the rock that you have in the tank?