Need advice... do I need airstone for planted tank?

[gw11ucb]

I have a 90 gallons planted tank. It houses 17 discus, various catfish, and tetra. Everytime I turn off the airstone all the fishes grasping for air. Why is that? I have a co2 setup. I set it up where 1 bubble every 8 seconds. my Ph is or around 6.0. I have two filters, xp3 and xp2. UV sterilizer hook up to the xp2. I need advice.

Thanks..

here is a picture of the tank....
http://f2.pg.photos.yahoo.com/ph/bou...;.dnm=e7fa.jpg

[Tonyd]

Nice tank, great fish. It is possible to have too little surface movement to get enough gas exchange. It is true that with a CO2 injected system you want to minimize surface agitation to keep the CO2 in, but you have to strike a balance with some surface movement for O2 exchange. In a heavily planted tank the plants help out a lot with the O2 production and exchange of O2 with the air may only be important and night, if at all. On a tank with less plants, just starting out, or lots of fish, the plants alone may be unable to keep up with the O2 demand. To me this seems most likely in your case. You didn't say what your CO2 was, but if you are maintaining a decent level with only 1 bubble every 8 seconds you may have too little gas exchange. I would recommend adjusting your filter return to try and agitate the surface a little bit more. See if that helps then try adjusting it again if needed.

Tony

[malkore]

how much light do you have over the tank? If you don't have much, then CO2 may not really be needed.

I have zero surface agitation on my 75, and keep CO2 at 1bps, for about 25ppm of CO2 on average. My fish never gasp for air. But, I have 3 watts per gallon, so the plants saturate the water with oxygen all day long.

[gw11ucb]

I have a total of 302 watts over my 90 gallon. two 96 watts (10,000k) one 55 watts 6700k and one plants growth blub (55 watts).

I just don't understand. Also, how do I raise my ph to at least a 6.8

[morpheus]

Hi there

You don't say what your CO2 concentration is. Easily worked out using kH and pH.

The other point that was raised is that your CO2 can be low but the dissloved oxygen in that tank could be low. The photo does not show that many plants and I wonder how much O2 they are adding to the water.

If they gasp then put the stone on and work out the CO2 concentration. Otherwise, add more plants.

Morpheus

[digger]

To get your plants to generate a considerable quanity of oxygen you'll need to fertilize them. What are your nitrate levels? What are you using for fertilizer?

[hubbahubbahehe]

SUP BOUN!!! good to see you on plantedtank finally!!!!

[LiquidEric]

You have a fairly high bio-load with 17 discus of various sizes. The fish by gasping are telling you they want more oxygen. I would add the airstone and turn up the CO2 if you need to. I doubt your CO2 is too high now with 1 bubble per 8 seconds. To raise your pH you could use a variety of buffers that will both raise pH and make pH more resistant to fluctuations. One product not the cheapest, but easy is proper pH
One 8.8 ounce bottle, which treats 200 gallons of water costs a little over $4.00. They also offer larger sizes of the product

[Fat Guy]

You're leaving out a huge factor here:

What is your KH?

[digger]

Originally Posted by LiquidEric

One product not the cheapest, but easy is proper pH

Proper pH is a phosphate buffer and will undoubtably cause algea blooms in a high light tank.

I've also heard, though I'm not sure of the accuracy of the statement, that proper pH will bind with trace mineral ions. Thus negating your trace fertalizers.

[LiquidEric]

Originally Posted by digger

Proper pH is a phosphate buffer and will undoubtably cause algea blooms in a high light tank.

I've also heard, though I'm not sure of the accuracy of the statement, that proper pH will bind with trace mineral ions. Thus negating your trace fertalizers.

Thanks, for the warning. I read one place that proper pH doesn't contain phosphates. If it does contain phosphates then I would avoid it. Just goes to show it's always good to check advice before you follow it .

[gw11ucb]

Thanks guy.. I will check my KH, GH, and PH right now. I'll post it up later on tonight. I don't want my PH to drop so quickly because I don't want to harm my discus.

[gw11ucb]

here is the test....
PH is at 6.0
KH is between 2 and 3
GH is at 7..

is there any other test I need to run. should I turn my co2 up... i have a 90 gallon...how much discus buffer and neutral regulator should I use?

thanks... hey hubbahubba... good to see you on here too@!!!!!

[LiquidEric]

Originally Posted by digger

Proper pH is a phosphate buffer and will undoubtably cause algea blooms in a high light tank.

I've also heard, though I'm not sure of the accuracy of the statement, that proper pH will bind with trace mineral ions. Thus negating your trace fertalizers.

I just looked at a bottle of proper pH(the 8.2pH variety) and the bottle says it contains no phospates, but you can do you own research to make sure. As for trace elements I don't know if it effects them anymore than any other buffer would.