Gas Those Fish!?

[mrjezzi]

I took delivery of my new pressurised CO2 system yesterday from LunaPet GmBH. Its the 2kg system with a Spiro 9000 Diffuser for up to 300 litre tanks and has nighttime shut-off. My tank is a 125 litre and had 2 Hagen Yeast CO2 systems with ladders. I took these out last night and fitted the CO2 and ran it very conservatively for the final 2 hours of the light cycle.

I checked after the lights went off that the CO2 stopped and it definitely had. This morning I wake up to gasping fish and 1 dead one....

The only thing I can think is that i adjusted the nozzle of the filter outlet to point slightly downwards to push the CO2 bubbles around the tank a bit more. Is there anything else I could have done? PH last night was about 6.3-6.4 and the KH was 10. fish all fine... checked levels today and the pH is about the same and the KH has fallen. I should point out that last nights figure calculates to 150ish ppm of CO2 which therefore can't be right! Any ideas appreciated! There is currently a bubbler in the tank to avoid further disaster

 

[xxBarneyxx]

It definetly seems that you overdid it with the CO2. The PH and KH can be effected by other factors (such as buffering effects in the substrate) so using the PH and KH of the tank water is not 100% accurate way of working out your CO2.

The best option is to get a drop checker and use a 4dKH reference solution. It will cost a max of £20 to get everything and once you have it then you will have another of everythign to last you a couple of years.

In the short term are you using a bubble counter on the CO2? This is not an accurate measurement either but if you start the CO2 off at 1 bubble per second you should be ok. If you was higher then 3-4 bubbles per second you probably added to much.

 

[Themuleous]

Yeh I agree. Sounds like changing the filter outlet had the desired effect rather too well! I run my 90lt tank at around 1 bps, so suggest you start at that and increase it gradually.

I second the call for a drop checker. Simple, easy to use and gives a instantly checkable guide as to the CO2 levels in your tank.

Sam

 

[mrjezzi]

Yeh I agree. Sounds like changing the filter outlet had the desired effect rather too well! I run my 90lt tank at around 1 bps, so suggest you start at that and increase it gradually.

I second the call for a drop checker. Simple, easy to use and gives a instantly checkable guide as to the CO2 levels in your tank.

Sam

Thanks Sam / Barney, I ordered a CO2 indicator from plantsalive.co.uk and I've just been rung to say that it is at home. Will dash home at lunch and stick it on! I really added the CO2 slowly and I think it is mostly to do with the angle of the filter outlet as the CO2 was definitely off overnight and they were fine at 10pm yesterday. Thanks agaain for everyone's help! I'll try and post some pics when its all set up properly and looking healthy!

 

[piper]

Did the exact same thing on Monday.

I directed my spray bar down to get the CO2 on my Hair grass woke up the next day to find all my fish gasping at the surafce. Stuck in a air stone while I went to work, when I got home a put the spray bar back in its orginal location.

All happy again; except for the amano shrimp who all commited suicide by jumping out the tank

 

[mrjezzi]

Did the exact same thing on Monday.

I directed my spray bar down to get the CO2 on my Hair grass woke up the next day to find all my fish gasping at the surafce. Stuck in a air stone while I went to work, when I got home a put the spray bar back in its orginal location.

All happy again; except for the amano shrimp who all commited suicide by jumping out the tank

Whoops! Its clearly quite easily done - I am amazed that pointing the filter outlet down makes that much difference. Went home at lunch and put the CO2 indicator (Red Sea) in and within minutes it had gone very blue so the bubbler I put in this morning and the filter outlet pointing up(ish) again certainly fixed the problem. Just one tetra casualty. Now that I can measure the CO2 properly its just a matter of gently increasing it.

I bought another couple of timers over the weekend, does anyone think I should put the CO2 to come on with the normal lighting (12.00 til 2200) as it is at the moment or on with the high light burst (15.00 til 19.00) or on a new timer to run maybe 11.00 or 11.30 til 21.00 for instance? Normal light is 2wpg and high light is about 3wpg. EI dosing etc. Tank is heavily planted!!! New tiger lilys turned up today - not very impressed! They weren't that expensive but they are barely plants (and 1 of them is broken in a couple of places). I won't shame the company on here though.

 

[Themuleous]

Set the CO2 to come on around an hour before the first set of lights, so say 11am. That gives the co2 level in the tank time to reach the desired 30ppm in time for the plants to start needing it. It can be turned off at the same time as the lights, so 10pm.

Sam

 

[garuf]

well I never! didn't realise co2 should go off with the lights I have mine coming on and going off 2 hours before the lights