CO2 injection setup questions

[Plowboy91]

I have a 150 gal tank that I am going to install a CO2 injection system into with a 5 lb cylinder, a Milwaukee Regulator/solenoid/bubble counter (MA957), a Milwaukee pH controller (SMS122), an Aquamedic 1000 CO2 Reactor and a Maxi-Jet 1200 Powerhead for circulation (295gph).

Is this power head too big for what I am going to use it for? The next model down is the 900 series with 230 gph. I don't have any experience with PH for circulation so I am hesitant to get one that is too small or big.

I was also wondering what is the best setting for my injection system once it is setup?


Thanks

 

[rkilling1]

Depending on the filter/filters you are running, you may not need a PH for circulation.

You also may want to look into a larger CO2 tank. A 5 pounder isn't going to last you very long with that size tank. (depending on what lighting you have and amount of plants.)

What do you mean by 'best setting'? pH, bubbles per second, pressure, ect..

 

[Plowboy91]

Well I have an Eheim 2217 which pumps 265 gph but i would need a PH to circulate the water through the reactor. I will probably upgrade to a 10lb CO2 tank then. Well my tank pH now is 6.8 and I don't think I want to change that much if at all. I am unfamiliar with this system so i don't know how many bubbles per second or what pressure i should run. I have 2-36" triple tube with 4 tropic sun bulbs and 2 reef sun bulbs. I don't have a lot of plants but i am hoping to get a bunch more once i get this system set up.

 

[rich311k]

You could put the reactor inline on the return from the filter and eliminate the need for a closed loop via a powerhead. Get an inline heater and you will have no equipment in the tank.

 

[Plowboy91]

That's something I hadn't considered but I am worried that there is not enough water circulation in the tank. I already have the heating issue covered so I wouldn't put an inline heater in at this point. Is it better to have more circulation than too little?

 

[Purrbox]

It's better to have a little extra circlulation IMO. With too little circulation you run the risk of nutrients not getting distributed evenly, which can lead to nasty algae like BGA.

If you are going to be injecting CO2, your pH will drop. This is a given. Ideally, you'll want a 1 point drop from your rested pH which sounds like it is 6.8. So you would want to drop it to 5.8 which would give you 30ppm of CO2. Please keep in mind that pH changes due to CO2 injection do not affect the fish the same way that pH changes caused by other factors would.

 

[rkilling1]

I have 2-36" triple tube with 4 tropic sun bulbs and 2 reef sun bulbs. I don't have a lot of plants but i am hoping to get a bunch more once i get this system set up.

That's not much lighting at all. Each tube is 25 watt's and the reef sun ones are 50/50's. So you are only looking at 125 total watts from your lighting. That's not even 1 WPG. If you want to grow many different plants, I would look into getting your lighting up to the 2 WPG range or more.

 

[Plowboy91]

Is this pH change going to the affect the absorbsion of nutrients for the plants or is 5.8 still ok to run a tank.

 

[7Enigma]

Is this pH change going to the affect the absorbsion of nutrients for the plants or is 5.8 still ok to run a tank.

The plants will be fine. It is the *possible* effect on bacteria that I was concerned about in your same situation. I decided to slightly buffer my water with baking soda at each water change so that my starting pH was higher. Then under injection (I have my CO2/PH/lights come on at the same time) the pH doesn't get so low. Since we dose ferts its just one more quick thing at each water change to take care of.

HTH

 

[Plowboy91]

So how much baking soda do you use per how many gallons you add in order to buffer the system?

 

[7Enigma]

I use 1/4 teaspoon per 5 gallons of water. I forget exactly what this works out to, but I believe it is somewhere around +3 degrees KH.

 

[Plowboy91]

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I thought there were more factors than just going by the WPG rule. If not then what lighting do you reccommend? Power compact w/ straightpin bulbs? I would rather not go to MH bulbs. It also poses the issue that I have 2-36" triple tube with 4 tropic sun bulbs and 2 reef sun bulbs that are practically brand new that i can't use.

 

[7Enigma]

I thought there were more factors than just going by the WPG rule. If not then what lighting do you reccommend? Power compact w/ straightpin bulbs? I would rather not go to MH bulbs. It also poses the issue that I have 2-36" triple tube with 4 tropic sun bulbs and 2 reef sun bulbs that are practically brand new that i can't use.

There are correction factors and such based on the type of bulb, as well as the tank dimensions (actual lumens hitting the plants), but unless dealing with a massive tank (or massively tall) or a nano tank the wpg rule is a pretty good starting point.

And as rkilling1 mentioned you have a very low light level right now. I would recommend at the minimum replacing the 2 reef lights (50/50's) with daylight bulbs. What is the temperature rating in k of the tropic sun bulbs? Most likely they are either 6700k or 10000k. I would recommend getting the other choice for the remaining 2 so you have a better balance of light. The 6700k are very bright and yellow while the 10000k have a blue hue to them. IMO a mix of the 2 would look very nice and put you at 150w which is 1wpg which in your tank is probably slightly over 1wpg true due to the size. Still not high enough for many species of plants but you could have a good mix of nice looking ones.

That's your only cheap option. Anything else requires at a minimum a ballast and bulb replacement, unless there is room for another housing where you could fit a HO T5 or CF bulb. While it might not look great getting a 24 or 48" single strip CF would bump you up 65-130w putting you much closer to 2wpg allowing your choices of plants to go up greatly.