My tank parameters - advice

[troppo]

Hi all,

Thought I'd post most water parameters and hopefully get some advice regarding areas I need to target. Any comments are much appreciated.

Firstly is my tap parameters (sorry, I don't have a chlorine/amine kit yet). It has been aged over two nights before the test this morning:
TDS = 167ppm
Ammonia = <0.25ppm
Nitrate = 0ppm
Nitrite = 0ppm
pH = ~7.6
GH = 71ppm/4dKH
KH = 54ppm/3dKH
Phosphate = <0.1ppm

Next is my tank water. Last water change was Saturday, almost 48hrs.

TDS = 233ppm
Ammonia = 0.25-0.5ppm
Nitrate = 0ppm
Nitrite = 0ppm
pH = 6.8-7
GH = 90ppm/5dKH
KH = 36ppm/2dKH
Phosphate = ~0.5ppm

Is there any anomalies in that data which I might need to investigate? The GH and KH have moved in opposite directions; is that right?
Otherwise are there any problems with the tank parameters and how I might correct them with modification to the tap parameters?
The tank is 5x1.5x2 and I do a weekly 50-60% water change. I am on the hunt for some drums so I can age my water pus I have an RO unit from my reef tank days so I can try mixing but Id prefer not to as then I'd probably have to start dosing trace elements aswell.

Again, any advice appreciated.

Cheers

[Hollowman]

The worry for me troppo is that you are showing Ammonia and no NitrIte or NitrAte. Edit, ammonia below a ph7 will be in the form of less toxic ammonium, but still a worry.
To me it suggests a brand new system, or something isn't quite right. Ammonia is the first stage of the nitrogen cycle, (ammonia is toxic) it is converted by nitrifying bacteria into NitrItes (also toxic at low levels) the final stage of the cycle chsnges the NitrItes into NitrAtes, which are not toxic in low levels.
Showing some ammonia and no nitirtes is not good imo. You should be aiming on a mature system for zero Ammonia and NitrIte and around 10-20ppm NitrAte. This to me is right and shows a mature filter system. Maybe try your nitrAte test again to check that result. It maybe you mis-read it. Are you using liquid tests?
Values may change in a planted tank system, but I am not a plant man, maybe ILLUSN can help there, but ammonia is bad in whatever value you have.
hth
Steve

[troppo]

Indeed it is a new system being only a few months old. I'm sure I went through a cycle though that said I had a rise in ammonia and nitrite but not nitrate. I used ammonia to pre-empt the cycle, maybe that had something to do with it...
I'll try the nitrate test again. I could've mucked it up or misread it.
I use liquid test kits. The API brand.

Cheers

P.S. - Should I be adjusting my tap water in any way before doing the water change?

[Hollowman]

when you say it is a new system, how long were you feeding the ammonia for? I fed my sump for 5 weeks until I could feed to show 4ppm in the morning, and 8 hours later there was none.