Newbie: Poor fish appetite, CO2 problem?

[ptero]

Hi. This is my very first post, so pardon me if I make any gaffes.

I guess I want to post the test results of the water here to see if anyone can tell me if it explains why my fish aren't eating voraciously like they used to. Or if there's any other advice for it at all.

Beginners Info Sheet
++++++++++++++++++

Tank Dimensions (LxWxH): 60x30x30
Lighting Intensity(No of Watts) : 2X36
Type of Lighting (FL/PL/MH) : PL
No. of Hours your light is on: 8
CO2 Injection Rate (bps) : 1 bubble every 6-8 seconds
Type of CO2 (DIY/Liquid/Tank) : DIY using Nutrafin setup
Method of Injection (e.g. Diffusor/Reactor): Nutrafin "flipper"
Substrate Used : Black gravel 1-3mm
How Thick is your base fert : NA, but put in a couple of JBL 7 Balls
How thick is your gravel : 4 cm at the front, 8 at the rear
Liquid Fertilizers Used : Tetra Florapride
Frequency of fertilization : 5ml with weekly 30% water change, thinking of using less
Tank Temperature : Dunno, breezy room
Type of Filter (overhead/internal/canister) : internal
Filter media used : black sponge provided
How long has your tank been set up : about 2 weeks (but using very old gravel from last setup, containing quite a bit of detritus)


Chemical Properties (Fill what you can)
---------------------------------------

Carbonate Hardness (kh): 40
Total Hardness (gH): 75
PH : 5.0
NH4 (ppm): 0
NO2 (ppm): 0
NO3 (ppm): 20
PO4 (ppm): Dunno
Fe (ppm): Dunno

Bioload (Your Fish and Plants)
------------------------------

Wisteria
Red Alterna... something I think, or is it Ludwigia...something
Cambomba
Red Tiger Lotus
Bacopa
Straight Val
Some strange looking curly red crypt(I think)

1 old zebra danio
1 old glass catfish
11 cardinals
4 otos
5 cherry barbs
3 platies


Describe your problem :

Fish not interested in eating. Cherry barbs pick up scraps though. Some brown algae on older plants (Cambomba and Wisteria). Some green spots too. Thought it could be the pH, so added one branch of coral into the filter box.

[mordrake]

what test kits are you using?
i don't think the ph, kh and gh readings are correct.
i used nutrafin co2 before and the ph hardly drops below 6.5

a tell tale sign of co2 poisoning: fishes gasping for air at the water surface.

[ptero]

Thanks Mordrake for the reply

No there's no gasping, but my all the ten Yamano shrimp I bought died after one day, and all my SAE (7?) died over a week period.

No gasping at the surface either. The platies sometimes lurk there and move when pestered by an oto. One of my glass catfish with an apparent bladder problem died... But the cardinals and cherry barbs stay mostly at the lower half of the tank. Maybe I should starve them for a day or two?

Test kits used were Jungle 5-in-1 Quick Dip, Otto pH test, and Fritz Freshwater Ammonia test kit. The pH test is available down to 6.2 on the Jungle dip and that lower limit value is shown when it's used. So that's corroboration for you.

In my first post, I mentioned there's some detritus in the substrate. This is accumulated mulm from the previous setup left to fester under neglect... algae grew though two of the cardinals, one zebra danio, and two glass catfish survived. Read somewhere that bacteria activity can lead to drop in pH, and soft water too?

I had two CO2 sources initially. Started off with the Tetra Aquaplant Optimat CO2 depot thingy and got bored and added the Nutrafin, using a homebrew recipe (following the level guides in the container for sugar and water, plus a quarter teaspoon yeast and one teaspoon baking soda). The CO2 supply is evidently good, since pearling has been observed, especially from exposed roots and broken leaves. I've removed the Tetra setup and I still enjoy looking at them tiny bubbles rising in the tank (not on the flipper, though that's cute too).

Plant growth is good, but there's the algae on the Wisteria and the Cambomba, and the Bacopa as well. Maybe I should just dump the former two since the tank's apparently "cycled" (no ammonia and nitrite detected), and get some of the fancier plants. Any suggestions on this too?

[chua]

What??? A kh of 40ppm?

You sure about it.

Normally, we have kh in the range of 2 to 5ppm.

Yours are way too high.

Must be the coral chips you added it.

[PeterGwee]

Chua, ptero's KH is perfectly fine at 40ppm (2.2dkH)...just make sure it doesn't go down further though. For your info, 1dkH = 17.9ppm...

Regards
Peter Gwee

[padfoot]

Hmm wats the temperature?

[chua]

oops.

Thanks for the correction. Will keep that in mind.