View Full Version : poor co2 saturation

05-24-2010, 09:09 PM
so i set up my co2 injection on a 75 garden tank with discus about 2 weeks ago. i have the bubble rate at 1 bubble per sec. at one point i had it up to 3 bps with no change in the co2 reading. there are no leaks in the system. i can not get my drop checker to indicate any co2 to spite my efforts. i am using a glass diffuser that i now have directly under a powerhead which further chops it up and projects it across the tank. i have a fluval 305 and a hang on the back top fin with 2 aqua clear 50 powerheads on each end of the tank. the HOB filter disrupts the circular flow with in the tank as well as surface tension.

is the HOB the sole reason i am not getting the drop checker to read above blue. the drop checker indicates co2/green my 20 DIY garden tank so i know the stock soln. is good. also, the discus tank is running at 81 degrees. gas dissolves better at lower temps, right? so maybe it is a 2 fold situation of the HOB and the elevated temp? any thoughts before i haul off and drop the mother load on another fluval to replace the HOB on that side of the tank?

05-24-2010, 09:58 PM
try an inline PVC diffuser

I have no trouble getting the drop checker to turn greenish yellow (30 PPM CO2) on my 75. Probably about 4 or 5 BPS

The filter spray bar output is just below the surface, it doesn't make much of a difference.

05-24-2010, 10:27 PM
yeah that was my thinking as far as the HOB, essentially no splash. i made a pvc reactor hooked up to one of the power heads when i was running DIY co2 on this tank. guess i might have to pull that back out...quite unsightly. i thought the glass diffuser would be "wonderful"..donno 'bout that anymore. donny, chevybow, mentioned a particular powerhead that implements co2 really well. need to look in to that. glad to to hear running out for $200 filter is not imminent.

05-24-2010, 10:44 PM
You could also check out the Hagen elite (http://www.aquaticplantcentral.com/forumapc/diy-aquarium-projects/44053-tiny-super-efficient-co2-reactor.html) reactor. These diffuse co2 very well, and they cost about $10.

05-25-2010, 08:39 AM
that is the one donny mentioned,he mentioned it was at petco online and $10, how about that :). thanks!! guess that will be the next step. if that doesn't work, i guess i will try unplugging the HOB and see if that has any impact before i buy a 2nd fluval.

05-25-2010, 09:24 AM

I just have the output of my CO2 (DIY) bottle going into the bottom of a maxi-jet powerhead. No bubble counter. Always get the drop checker to show green...sometimes even yellow. I have nothing breaking the surface, but the output of the maxijet does ripple the top surface a bit. Have a marineland c-360 canister filtering the tank. I have, at times, thrown an aquaclear 50 HOB on the tank, with little or no affect on the CO2 levels..

'other' larry

Larry Bugg
05-25-2010, 09:38 AM
Here is what I use on all three of my Co2 tanks. Very easy to build.