Switching from aerator to co2

cmslick3

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Dec 27, 2005
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I've got a 20gal tank with 3 cichlids, 2 koi and 1 pleco. The tank parameters are:
Nitrate: 80+
Nitrite: 0.5
Hardness: 420
Alkalinity: 300
PH: 8.4
I know it's from test strips, I KNOW!
Ammonia 0 <- liquid test.
70 deg temp.

I'm using a Fluval 3+ in tank filter and I have the air going just a little bit all the time. My plants however are looking very poor. I've got 1 moss ball, an Anarchid, 2 broad leaf grasses, and a "Poppy" looks like a lilly without flower. I have been seriously thinking about adding co2 to the tank, but I am afraid of killing my fish. I have tried in the past to turn off the air and within a day the fish are gulping the surface. I know there are more than enough nutrients and light for the plants but it's obvious that the plants aren't using it.

I was going to do the DIY CO2 method and I have everything I need for that, but do you think I need more plants? Any ideas?
 
cmslick3 said:
I've got a 20gal tank with 3 cichlids, 2 koi and 1 pleco. The tank parameters are:
Nitrate: 80+
Nitrite: 0.5
Hardness: 420
Alkalinity: 300
PH: 8.4
I know it's from test strips, I KNOW!
Ammonia 0 <- liquid test.
70 deg temp.

I'm using a Fluval 3+ in tank filter and I have the air going just a little bit all the time. My plants however are looking very poor. I've got 1 moss ball, an Anarchid, 2 broad leaf grasses, and a "Poppy" looks like a lilly without flower. I have been seriously thinking about adding co2 to the tank, but I am afraid of killing my fish. I have tried in the past to turn off the air and within a day the fish are gulping the surface. I know there are more than enough nutrients and light for the plants but it's obvious that the plants aren't using it.

I was going to do the DIY CO2 method and I have everything I need for that, but do you think I need more plants? Any ideas?
Oh yeah, I got ideas. You may not like them though... But mostly, I have questions...

How long has this tank been set up?
You have 3 cichlids? Could you be more specific?
Cichlids and Koi? Cichlids are warm water, Koi are cold water. Bad mix.
What kind of Pleco? Unless it's a smaller type, the tank is way too small.
Nitrate is 80+??????? Man, I have a cow if mine get to 10. Water changes. ASAP. big ones. Get the Nitrates down to below 20 at least.
Nitrite is .5??? When you are doing a fishy cycle, you never want to see Nitrite over .25. You've got double that.
The fish are gasping at the surface because the water is foul, and probably oxygen depleted as well. Water changes will remedy this. The high Nitrite could be a factor in this, you may have high ammonia as well. That would do it as well.
What's the ammonia level?
Is this tank cycled? Has it had a major change in inhabitants, filter/filter media recently?
Plants are not intended for sewage treatment. They will use some Nitrate, etc, but you still have to change water.
How much light do you have? What kind of bulb? The wrong kind of light is the same as no light.

Bottom line, and IMHO, the Koi need to be separate from the Cichlids. Major water changes are called for. The tanks does not appear to be cycled.

EDIT OK, just saw where you said Ammonia = 0
 
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I have been seriously thinking about adding co2 to the tank, but I am afraid of killing my fish.
you'd do better to get a larger tank and remove the koi to a separate 'cold water' tank .. koi are not tropical fish. your current conditions are going to kill your fish.

get the nitrates down to 10 ppm or less by 50 percent water changes on a weekly basis at minimum.
 
The Koi are not perminant residents, come spring they are out. The 3 Cichlids are Lake Malawi kind. There are 2 bright orange with no strupes, one slightly yellow with black speckles. The Pleco is a normal dark borwn speckled guy... he will likely be going with the Koi. I do not have the ability right now to seperate the Koi and Pleco, I'm trying to get approval for a small perminent outdoor pond they can live in for now.

The tank has been setup for 3 months now, the values as I indicated are off of test strips so thats why my accuracy is bad. I usually change 50 % water every couple weeks. Everything has been stable like this for at least the last month and the fish all seem to be doing fine. They only gasp at the surface if I turn off the air. The light is an fluorescent aquarium type bulb that came with the hood, Not sure on watts right now, may need to be changed I guess.
 
cmslick3 said:
They only gasp at the surface if I turn off the air
Other than to appease my wife, who liked the look of a bubble curtain, I don't think I've run aeration in a tank in over twenty years. It isn't necessary.

Contrary to myth, airstones do not put oxygen into the water. They do, however cause rillples on the surface. This allows for more surface area for natural gas exchange.

Were the Koi recently added?
 
No the Koi came in at the same time the Chichlids did. I did this to make sure there was no shock to the tank as you are elluding to. I know that the air stones only help stir the water and thats why I don't understand the fish reaction to my turning off the air. The Koi are both about 3", same with 2 Cichlids, 1 Cichlid is roughly 2", and the Pleco is about 3". I know the 1 inch per gallon thing is bogus, I'm not going by that I just had the need to put the outside fish inside, knowing that it was going to require more changes and filtration hence the oversized filter and cleaning it every other week.

I don't see how the Koi being in the 70 degree water is hurting anything, they normally can withsand a range from 80 to 40 degrees, given that it's normally 70 in there I don't see an issue there.
 
you need to find a new home for the koi. do you have a heater? cichlids of any kind should not be in water colder then 75 degrees, and most like it warmer, around 77-80

you need to change at least 50% of your water, more is preferable. even though nirtrate is not very toxic, it can be in very high levels.

do not add any CO2. plants will love it in your tank because of all of the CO2 in it already and because of the high nitrates, and should be fine for a long time. you still need to do a water change to get it down to 20, and the plants you put in will have plenty dont worry.

BTW, how often do you do water changes?
 
CaptnDan said:
Nitrate is 80+??????? Man, I have a cow if mine get to 10. Water changes. ASAP. big ones. Get the Nitrates down to below 20 at least.
I'd suggest to do this more slowly. The fish are probably used to those conditions and won't take sudden changes very well, although I agree with the goal.
CaptnDan said:
Contrary to myth, airstones do not put oxygen into the water.
I suspect this all depends on concentration gradients. If the oxygen level in the tank is very low, airstones will help. I'd really like to see what this "myth" talk is based on.
 
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