Huge drop in PH

[Bloo]

OK, I think I have a big problem. Or maybe not....
Well a few days ago I added a CO2 Hagen Natural Plant system to my one tank. I've never used CO2 before and though I knew it would bring my PH down, I did not expect to reduce it from 8.2 to 7.2 in a matter of 3 days. Is this normal ?
All other stats are absolutely fine (Ammonia & Nitrite 0 and Nitrate 20).
KH is 11 spot on - hard !

Well this evening one of my lovely L255's was belly up I am shocked an horrified and angry that I could have caused his death
Did I ?
I did a 30% water change and the other one in the tank seems to be fine (and not distressed in any way), but I'm very worried now. I don't want to stop the CO2 either and cause the PH to go right back up again either. What to do - if anything

Ps: the CO2 mixture is measure exactly as per the instructions and everything seems to be working fine in that respect. I'm not overdosing on CO2 either. Is the exact right amount for the size tank.

 

[WILDER]

I don't no if this will help or not.
http/www.thekrib.com/Plants/CO2/kh-ph-co2-chart.html
http/www.aquariumsite.com/freshwater/chemistry.php

 

[smithrc]

as long as the PH change did happen over a few days it shouldn't have caused a problem. If it happened over night then it will have been too quick.
how is everyone looking now? if they are ok as things are, dont remove the co2 or it will just swing the other way.

get a tube clamp and try to limit the co2 flow so you can control the PH shift over a longer period

 

[Bloo]

Well I just thought I'd report back. The other 5 fish in the tank are fine and the remaining Medusa plec is fine too. Perhaps the one that died was just a lot more sensitive to PH changes
However, I definitely link his death to the PH change, as he was 100% healthy in all other ways
I'm still gutted. I'll have to get a couple more when funds allow.

The PH now seems stable at around 7.2 / 7.4

 

[rdd1952]

That seems like an extreme drop in pH for that type CO2 system. I bought one a while back and put it in my 29 gallon. My pH was 6.8 with KH of <1 (yellow with first drop, never turned blue at all). My pH only dropped about .6 in a week but I took it out because I was afraid it would continue to drop.

 

[Bloo]

Yes, that's exactly what I thought. I never expected it to drop that much in a couple of days Especially as my KH is 11 and my GH is about 20 !
I'm still very upset and annoyed that he died - annoyed at who or what I don't know.

This is him dead

 

[smithrc]

thats the think i dont like about plecs - the dont look dead!

Our 264 still looked fine when she went

That was a lovely fish -