Water perimeters. HELP!

[Fenton]

Hi, I know I'm new here but have been keeping tropical fish for over 18 months now and NEED to get this sorted! I have a 6x2x2 tank. Been set up for a week but I used my previous water, driftwood and live plants from my previous 5x1.5x1.5 tank. The tank I've had now was used before for 12 months has a sump filter which is 4 long x 1 hight x 1.5 front to back with 61(I've counted as I added them) bio balls. UV steriliser which were also used in the set up from the guy I got my new tank from, along with the gravel (I've added 25kg aquarium sand).
When transferring, the water parameters were how they are now but this is what I was used to with my old tank. So I added my stock;
2 oscars -8inch length
1bgk - 10 inch
1burcher - 7inch
1bala shark 7inch (may be rehomed if too many fish)
1plec - 8 inch

i am more than aware I can't keep all these in this tank when fully grown so unless it ruining my water now, I would appreciate not being told about it. Planning a 2nd tank - same size in 6 months time for the burgher and BGK.

So, my problem ammonia 0.25. 0.00 if held to a light, not held against the card.
NitrAte. 15 mg/litre
nitrIte 0.00
PH 6.8 I know this isn't neutral but I'm told and have read its what the black ghost likes
chlorine 0.00.



Now. Is the nitrAte ok at 15?
is the ammonia best read against the card or the light? (no green at all in the light)
is my tank and filter adequate for my stock?


Really appreciate the time you take reading this essay and the answers to come.

 

[ElectricBlueSeanBurch]

Post pics of your test results. Ammonia should be 0. Nitrate <40ppm is ok. <20ppm is better. So you aren't doing to bad there. Stocking sounds fine to me, at least for awhile. Might need more bio media if all you have is the bioballs.

 

[Fenton]

Thanks for your reply. Can't believe I got one so quick.
There is also 6 sponges, 2before the bio balls which are thin, 2after which are medium, then 2before the return then what can only be described as a huge industrial sock which the water returned from the UV filter goes into which then penetrates back into the sump, does this sound efficient enough of do I need to get a few more things? The water is crystal, I could read a newspaper through it. But I know this isn't the be all and end all.

 

[Fenton]

As you can see, (just,as the 2nd pic was a mission to take with my iPad) in proper light, the result is definitely 0.00for ammonia.