Is high light without CO2 a problem?

Stefanie

Stefanie

AC Members
Jan 12, 2005
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16
Maryland
I would like to upgrade the light on my tanks (currently with standard light) to either compact fluorescent or at least a double strip light. I am very new to keeping fish and even newer to trying plants. This is why I would like to avoid adding CO2, because I am afraid to mess up my pH. Is this asking for trouble? Am I going to risk an algae bloom, or will it be beneficial?
So far my plants are growing OK... not great but OK. Algae is present, but not overwhelming (still some diatoms (newly set up tank) and a bit of bba). If more light would increase algae rather than helping my plants, I would opt for keeping it like it is...
 
You can use flourish excel to add carbon. I stopped my diy co2 two weeks ago and have been adding excel, just a tad more than the recommended dosage and the plants are growing just as fast. I trimmed yesterday so the fish have room to swim. My green tiger lotus is about 10 inches wide. I removed 2 breadplate sized leaves yesterday. Flourish excel alone does work.
It also keeps algae in check. I don't think I'll go back to co2. I need camera batteries, but wil post a new pic when I do.
So, yes you can have higher lighting but will need to add carbon in some form. Flourish excel is easy. For fert, I'm using flourish comprehensive. NPK when needed.
 
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Here's how I look at it: fertilization, CO2 (or another source of carbon like Excel), and light form a triangle. All three have to be in balance with each other, or the whole thing falls apart. If you want high light, say 4WPG, it can be tricky to keep things in balance. I would have said certainly you'll need CO2, but SF seems to be making it work with just Excel - I think the important part is that the plants have a good, steady source of carbon. The other essential component is fertilization - whether you mix your own or use commercial preparations, you'll need to provide the plants with trace elements and macro nutrients to keep them healthy (when it comes to macros, IME, under high light the PO4 and NO3 produced by the fish are not nearly enough for the plants, you may need to provide these along with K and possibly Ca, Mg).
Any part of the 'triangle' that's missing or low - not enough light, a missing fert, too little carbon - will become the limiting factor for growth. When all three are in harmony, you'll see faster, healthy growth and very little algae; it's very much a balancing act.
 
Ditto to what Blinky said. I can share my own experience as a planted tank newbie... I've been with plastic plants in my 29gal for about 10 years... just converted it to planted by changing over to fluorite substrate and 65Watt Coralife giving me just over 2 WPG. I dose with:

- plain Fluorish
- Flourish Excel
- Flourish Iron (I have no way of measuring Iron and I've heard the kits are not accurate enuff, but went by seeing some plants leaning towards a more yellow and transparent color... so it seems some dosing has helped)

Without any CO2 injenction and just over 2 WPG, I am happy thus far this first month. My highlights: I have 4 baby amazon swords snipped off from the mother plant, a banana plant shooting up 2 runners with lillypads... I am now concerned I have too many amazons for my 29 gal... heh. So yes, I think it's a subtle balance between not having too much lighting, yet enough for the plants to grow and some mild dosing.

On your fear of algae... I have a couple of SAEs, otos and Japonica Shrimp to keep it under control... I still have to do some glass cleaning with the MAG floater every couple of weeks when I first see a few small spots, no big deal.

Fyi... I've also been very close to jumping into CO2 injection... but my KH is very low so I am in fear if big PH swings. I'm sticking to the above forumla for now.
 
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Thank you all for your input... I think I can live with Flourish Excel... or can this also mess up my pH? I have pretty hard water (about 280 ppm total hardness, and about 150 ppm kH). Is this too hard for plants? As for algae eaters I am pretty much stuck to cleaning myself, since I have dwarf puffers in this tank (see Avatar), and they dislike company :)
So, hopefully I can get this tank more interestingly planted... thank you again and sorry for all my silly questions... I am definitely not one with a "green thumb", and I have yet to check if I have at least a "wet thumb".
 
Flourish Excel is not the equivalent of pressurized CO2. It may be equal to DIY CO2 unless you use multiple, staggered-change fermentation bottles. The break point all depends on the balance, as Blinky pointed out. I need to supplement carbon somewhere between 2.3 and 3 W/gallon standard NO fluorescents at 12 hours/day. With more than 3W/gal., I am in trouble without pressurized CO2.

In general, aquatics plants do not care much how hard the water is.

Dwarf puffers generally ignore Otocinclus catfish, and if you are lucky will ignore Amano shrimp (but some DPs do eat them). Those are the two best small algae eaters that I use. My DPs even ignore rednose-redtail shrimp (which are not algae eaters - it was a mistake on my part to co-house them).
 
Excel nor any of the ferts has affected any of my water parameters. One rule I do keep at as I've read this dozens of times no matter which planted forum I surf... always dose less (maybe half) of what the bottle instructs you. At least this should be done initially... the idea to see how not only your plants react, but also how your tank will react.

And ditto also to what RTR is saying about Excel is not a CO2 substitute... but it cetainly won't hurt and I am happy with the results thus far.

on hardwater and plants... my water is also very hard... no worries there.
 
Be careful how you quote folks - I did not say "Excel is not a CO2 substitute". I said that it is not the equivalent of pressurized CO2, which is not the same thing at all. CO2 is a carbon source for aquatic plants. Excel is a different carbon source for aquatic plants, but is not the equivalent of pressurized CO2. It may well be better than some other techniques, depending on how they or the Excel are used.
 
I'd suggest for anyone, to add Excel or CO2 before adding MORE light.
Unless the light is grossly under the limit, most will do better by adding CO2 and not have the issue the rest have when they try and add 4-5w/gal of light and have trouble.

Adding CO2 increases the efficiency that plants cna use less light.
Algae will not grow well at lower light.

More light = more uptake demand.
More light also = more algae
More light = more dosing
More light = more pruning.

I'm snot sure why folks seem to feel more is better.

Regards,
Tom Barr
 
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