Test Readings [8 Month Tank]

[jelliebean]

please could someone tell me what the best test readings should be for a 8 month old tank [tetra test 5 in 1 strips]??
i.e.
No3 - [mg/l] - 0, 10, 25, 50, 100, or 250 ???
No2 - [mg/l] - 0, 1, 5 or 10 ???
GH - <3d, >6d, >10d or 16d ???
KH - 0d, 3d, 6d, 10d, 15d or 20d ???
PH - 6.4, 6.8d, 7.3d, 7.6d, 8.0 or 8.4 ???

I am confused with all the different advise on different websites, and wondered what they are supposed to be ??

 

[Colin_T]

mg/l is the same as ppm.

NO3 is nitrate and you want to keep that as low as possible. However if you have nitrate in your tap water then just try to keep it at the same level as the tap water. Levels over 50ppm can cause issues to some fish and will cause problems to invertebrates like shrimp and corals.

NO2 is nitrite and you want to keep that on 0 at all times. It might go up a fraction (to 0.5) for a short time after feeding but it should come down to 0 within an hour or so. Any reading above 0 will cause stress to the fish. the higher the reading the more damage that will occur to the fish.

NH3 is ammonia and NH4 is ammonium. NH3 occurs in alkaline water and NH4 occurs in acid water. You want this to be 0 at all times. Any reading can cause problems to fish and high readings are often associated with over feeding, poor tank maintenance, or washing out the filter under tap water.

GH is general hardness and can vary between 0 and 400ppm. It depends on what the tap water is and what fish you are keeping. If you have Tanganyikan cichlids then they want hard water around 350-400ppm of GH. If you keep wild caught discus or wild angelfish then you want soft water with a GH below 150ppm. However if you are keeping most community fishes, and the fishes are captive bred, then a GH between 100-300ppm (approx 6dgh - 16dgh) is fine.
1degree GH = 17.9ppm.

KH is carbonate hardness and you want that to be 6degrees KH or higher. The KH stops the PH from dropping. If you have no KH in the water the PH can go acidic (below 7.0) very quickly.
again 1degree KH = 17.9ppm.

PH can vary between 1 & 14 however most freshwater aquarium fishes do best at a PH of 7.0. They usually tolerate a PH between 6.0 & 8.0. Some species come from alkaline water (PH above 7.0) and other naturally occur in acid water. If you are keeping wild caught fishes then try to keep them in water with a similar PH to what they have in the wild.
ie: wild discus live in water with a PH between 5.5 & 6.8.
ie: wild caught cichlids from Lake Tanganyika occur in water with a PH between 8.5 & 9.0.
If you are keeping a general community tank then try to keep the PH around 7.0. If your tap water has a PH of 7.5 then just accept it and use it as is. Most fish will be fine in that sort of PH.