90G unattended Co2 or excel?

pacific12977

Junior Poster
Sep 15, 2008
9
0
1
Looking for alittle advise on a 90G planted tank I am setting up. Alittle about the tank..flourite substrate and I have 4x54w of T5Ho available for lighting and am planning on a fairly heavy plant load. It comes down to this...CO2 or excel as a carbon source and the catch is I work out of town numerous times in the summer for up to a month at a time. I would love to have the growth and beauty of a co2 tank, but is it possibl to leave it unattended for 30 days at a time? (Gf will be there in case of emergency, but knows nothing about aquariums!!) Could this work if i used a fert doser or 2 maybe, one for macro and one for trace? could it work with 4 weeks between water changes ? Or would it be better off going with excel and hoping the tank will turn out ok. Thanks alot!
 

Carissa

Guru Class Expert
Jun 8, 2007
678
0
16
In that situation, if it was me, I would go low-tech. High light like that can cause problems to occur really fast if something goes awry. I would be afraid to leave a tank for a week with lighting like that, much less a month, and that with no water changes. A non-co2 or Excel tank with low light (maybe half what you have there) and a rich substrate will be much more forgiving. A month is a long time for any tank to go without water changes, much less a planted tank and high-tech at that. My .02 anyway. Non-co2 tanks can be very nice, without nearly as much hassle. The lighting is the issue here I think, that determines the speed at which things take place.
 

SpeedEuphoria

Prolific Poster
Aug 16, 2008
32
0
6
I agree with most of the above, I think CO2 is out of the question. You could use excel when your around. Also turning the lights down to a reasonable amount of hours while your gone should help.

I'm not sure that that light would be too much? but maybe you coulds only run 2 bulbs while your gone?
 

VaughnH

Lifetime Charter Member
Lifetime Member
Jan 24, 2005
3,011
97
48
88
Sacramento, CA
Effectively you will have over 3 watts per gallon on that tank, far too much for an Excel only tank, and equally far too much to leave the tank unattended for 30 day periods. You would almost certainly return home to an algae filled mess the first time you left it. It is work and it can be tricky to use even less light than that, observing the tank every day, cleaning it weekly, doing water changes weekly, and hoping to get a good result. I agree with Carissa that you would be much happier with a no-CO2, low light tank, where everything happens over a much longer time span. Even then, 30 days is a long time to leave the tank unattended, except by an uninformed, un-motivated "helper".
 

Gerryd

Plant Guru Team
Lifetime Member
Sep 23, 2007
5,623
22
38
South Florida
I have to agree with the other replies, that a low tech, low-light setup would be better for you.

With high lighting and c02, you need to fertilize. With ferts, you need water changes.

I would go to 1 or 1.5 watts per gallon. See if you could mount the lights so that you can raise them a few inches when you are away. That will reduce the growth and nutrient requirements and make it a little easier.
 

pacific12977

Junior Poster
Sep 15, 2008
9
0
1
VaughnH;28990 said:
Effectively you will have over 3 watts per gallon on that tank, far too much for an Excel only tank, and equally far too much to leave the tank unattended for 30 day periods. You would almost certainly return home to an algae filled mess the first time you left it. It is work and it can be tricky to use even less light than that, observing the tank every day, cleaning it weekly, doing water changes weekly, and hoping to get a good result. I agree with Carissa that you would be much happier with a no-CO2, low light tank, where everything happens over a much longer time span. Even then, 30 days is a long time to leave the tank unattended, except by an uninformed, un-motivated "helper".

I agree the co2 is pushing it for this set up!! but It would only be 2.4 watts per gallon, which I dont think is too high, considering the 24in depth?? Im debating using the full four bulbs for maybe ony a few hours a day? Might work with excel?
And sorry but I really dont understand this unmotivated, uninformed helper comment?

Thanks for the help
 

VaughnH

Lifetime Charter Member
Lifetime Member
Jan 24, 2005
3,011
97
48
88
Sacramento, CA
Because you have T5 lights, I assume with individual reflectors for each bulb, you have at least 1.3 times more light per watt than the watts per gallon "rule" is based on. Possibly more than 1.5 times more light. So, the 2.4 watts per gallon is effectively at least 3.2 effective watts per gallon and possibly more than 3.6 effective watts per gallon. The depth of your 90 gallon tank is about what is normal for that size tank.

If you have someone looking after the tank, who is well versed in how to care for a high light tank, and well motivated to do the work involved, then you aren't really leaving the tank unattended for a month. But, from your description your "helper" doesn't know how to care for a high lighted tank, and, as a result I doubt that she would understand or be very sympathetic to the need for routine maintenance, pruning, cleaning, etc. that such a tank has to have. Undoubtably you could make this work, but it will be much more likely to succeed with lower light.
 

pacific12977

Junior Poster
Sep 15, 2008
9
0
1
I got you now, The tank is going to be low tech so it will require minimal attention when im gone. I've had lots of success leaving fish, and expensive picky ones at that, alone for long periods of time with just some one feeding them daily and they are very healthy. I think I can now make it work for a planted tank! I can set it up so it only requires weekly, or twice a week ferts only. I will be home now untill next summer so theres lots of time to get it up and running and stable.

The lighting I have is actully two 2X54w lighting fixtures with parabolic reflectors if that makes any difference.

Im still planning on using excel also. Could i use a doser for that and lower the dose and the lighting when im gone?? Just to slow it all down?

Also I will be using flourite for the substrate as I already have 6 bags of it sitting at home. I am going to use Leonardite as a first layer. How much should I use? I can by 1, 3, or 12 pound bags for between 12 and 65 bucks CAN.

And for plant load....whats a good number of plants to give me the best chance at success? I was thinking 50-65 to start?

Thanks for the help again
 

pacific12977

Junior Poster
Sep 15, 2008
9
0
1
Also would I get better results with the dry ferts like KNO3, KH2PO4, AND K2SO4 or using seachems line of ferts?

Or is it just the price thats the advantage?
 

VaughnH

Lifetime Charter Member
Lifetime Member
Jan 24, 2005
3,011
97
48
88
Sacramento, CA
"Low Tech" means low light intensity. You can't successfully reduce the plant growth rate by restricting fertilizers. You can only do that by restricting the light intensity. If you use only one of those two light fixtures you will have a chance to succeed. To do that I suggest reading about Diana Walstad's "el natural" method for running a planted tank. One place to do that is http://www.aquaticplantcentral.com/forumapc/el-natural/.
 

Carissa

Guru Class Expert
Jun 8, 2007
678
0
16
^ Further in explanation to Vaughn's comment above... the use of Excel or CO2 is not actually what drives the growth. It's the lighting that drives growth. Adding a source of carbon and other fertilizers is just something that you HAVE to do if you plan on driving your growth fast with high lighting. Slacking off on fertilizing (including carbon which is one type of fertilizer) while continuing to drive fast growth with the high lighting will quickly result in algae, deficiencies, and ultimately, die off. Think of the amount of light as the speed at which you are driving your car, and the fertilizers (carbon included) as the gas that you're putting in your tank. Putting less gas in your tank will not reduce the speed of your car, it will just get you into trouble if you run out. The only way to reduce the amount of gas you burn, is to drive less. Doing water changes is like doing the oil changes on your car. The more miles you put on it within a certain period of time, the more often and more crucial it is to do oil changes to keep it in good shape.

Personally I use the dry ferts, they're cheaper. I don't see any advantage to buying the Seachem line, it's doing basically the same thing.
 

pacific12977

Junior Poster
Sep 15, 2008
9
0
1
Yes, I understand what you guys are saying, but I think I was misunderstood on my last post. I did mention reducing the lighting intensity aswell.
Say you had 2 w/g and u used ferts 2 times a week. If you cut your lighting down to say 1-1.5 w/g and added fertilizer only once a week would that not just slow down the growth of the plants as long as there was the right balance?
If its the light and fertilizer that most important could you not kind of play around with the lighting levels and fertilizer levels to achieve different growth rates? Kind of like how plants might go through different seasons in the wild at different times of the year depending on whats available to them at that time?

Or am I completly off the wall on this?
 

Carissa

Guru Class Expert
Jun 8, 2007
678
0
16
Yes, you are right, reducing lighting reduces the need for fertilizers.

However, I would be a bit apprehensive about doing this. Plants thrive in a stable environment (especially when it comes to carbon). Suddenly decreasing the amount of carbon and light could still result in problems. Plants adapt to their circumstances to make the best use of what they have available, change is almost always a bad thing for plants and takes time to adapt to it. I don't think you would gain much by keeping your lighting high, if it means you have to start messing with it later on. If you are going to do this, I would test it a couple of times before you actually go away. Any change in conditions can cause problems so beware.

If you did decide to do this, I would definitely not reduce your carbon even if you lower lighting and other ferts. Reason being that plants adapt to the amount of carbon available, and if you go from high carbon to lower carbon, plants basically stop growing completely as they adapt, which can take a week to a month to do. During that time algae can easily start taking over, as the plants are suddenly at a standstill in growth with their handicap.

Another issue you have is that not all plants will do well under lower lighting. So plants that appear healthy, if you were to suddenly reduce lighting, could die off. Plant die off = algae, algae = more plant die off, and it just snowballs.

It's a very risky idea. I'm not saying it can't work, but in practice I would be surprised if you didn't have some problems.

A better idea would be to get your gf into planted tanks.... :)
 

pacific12977

Junior Poster
Sep 15, 2008
9
0
1
Alright, So I am going to try and find a stable balance of light (not the full 4 x54, as you say it is too much without co2) , fertilizer and excel that will work and can go a month with out water changes. I can use a doser for the excel and add ferts 1-2 times a week. I think this should be possible, but I guess I will have to play around with it and see.

Any recommendations for plant load? I know heavier is better, but whats heavy...100 plants in a 90 to start?
 

Carissa

Guru Class Expert
Jun 8, 2007
678
0
16
I guess it depends on the size of the plant....have a look at some pictures of fully planted tanks and keep buying plants until it looks right. :) Some fast growing stem plants are good to start off with. Think more about covering your substrate than looking at the height to start off with, the plants will grow taller to fill in the height but they are less likely to grow out to cover the substrate (depending on the plant naturally). If you spread out bunches of stem plants, they will grow faster than if you leave them bunched up. You can always bunch them up later on. For a lower lighting tank, I've had good success with java fern, crypts, and some hygrophila polysperma as a faster growing tall stem plant. Anubias are great too. Easy care, low fertilization requirements (except the hygro, which will suck up fertilizers faster since it also grows faster than the others). I'm actually happier with my tank since I changed to non-co2. It seems like before, I could never keep up with the pruning, and algae was always an issue since I was doing diy co2. Now, I have nearly 0 algae, the tank looks great all the time, not just after pruning. Plus I don't seem to have any issues going 2 weeks without a water change. You also want lots of algae eating fish, cuts down the maintenance considerably. I have 4 oto's in my 30g.
 

VaughnH

Lifetime Charter Member
Lifetime Member
Jan 24, 2005
3,011
97
48
88
Sacramento, CA
Heavy planting means a plant every square inch of substrate, if not more. So, if that 90 gallon tank has a substrate area of 900 square inches, heavy planting means planting 900 individual plants. That seems overwhelming, but if one of the plants is Glosso, for example, a single pot could have 100 plantlets in it, since you can plant cuttings that have only two leaves. And, a bunch of Rotala green could have 20 or more plants, since you can cut the stems in half and plant each half. Using tweezers to plant, planting with very little water in the tank, you soon get a rythm going and it doesn't take nearly as long as you might think.
 

pacific12977

Junior Poster
Sep 15, 2008
9
0
1
Well, thanks for all the help and I am going to start looking into some good plants to use!

Any ideas as to whats the best groundcover plants for low light?
 

VaughnH

Lifetime Charter Member
Lifetime Member
Jan 24, 2005
3,011
97
48
88
Sacramento, CA
pacific12977;29125 said:
Well, thanks for all the help and I am going to start looking into some good plants to use!

Any ideas as to whats the best groundcover plants for low light?

Marsilea minuta (PlantGeek.net - Marsilea minuta) is the best low light ground cover plant as far as I know. I had some problems getting it to start growing, but then it took off and made a big mass of ground cover. I did have high light at the time though.