Thanks, BiscuitSlayer, for the advice.
I thought you were going to take the low light approach and see how things pan out.
So if I want to go with a low-tech setup, I shouldnít add more lights? I was under the impression that even if I added another 7-13 watts of light, my tank would still be considered somewhat ďlow-light.Ē For a 6 gallon tank, what wattages are considered high, medium and low? I know the wpg rule doesnít apply to nanos, but a rough estimate would be useful.
Overall, itís probably a good idea for me to stick with a low-tech tank for now. I donít mind the extra work
involved with dosing ferts and CO2 regularly, but Iím trying to do everything as inexpensively as possible. Iím an unemployed grad student, so I donít really have the money for fancy CO2 equipment or anything like that. I wouldnít mind using a DIY CO2 injector, but they seem a little unpredictable (in terms of how much CO2 they give off), so Iím guessing that itís probably not the greatest idea to use one on such a tiny tank, right? Can I assume that excel (by itself) would not provide enough carbon for a 6 gal tank with 26 watts of light?
Are you talking about nitrites or nitrates?
I was talking about nitrates (my nitrites are at 0). Iím so used to keeping fish only tanks that itís kind of hard for me to accept the fact that nitrates arenít always bad, lol. In my unplanted tanks, the nitrates usually donít get above 10 ppm before itís time for their weekly water change.
As far as water changes go, I would change the water weekly. Thats me though. You might be able to get by with biweekly water changes.
Have you read the links Homer posted? I donít mind doing water changes (in fact, I actually enjoy doing them), but it seems to me that the information presented by Walstad and Barr suggests that frequent water changes are counterproductive in these sort of set-ups. Walstad suggests changing 50% of the water every six months. Barr explains that the reason for such infrequent water changes is that
ďDoing water changes adds CO2 back to a CO2 limited tank.
Plants and algae both can and do adapt to low CO2 environments and induce genes to make enzymes that concentrate CO2 around Rubisco, the CO2 fixing enzyme. When we add the CO2 at higher levels back, this causes the plants and algae to destroy the low CO2 enzymes and start growing without of them since they no longer need them to fix CO2 form the KH ( the -HCO3).
Why keep all this machinery around if you no longer need it? Doing weekly water changes "fools" the plants and helps encourage algae more. Algae are faster to respond to low CO2 than plants.
Once the plants do adapt, they can do well.Ē (Barrreport, 2005
So, if my nitrates arenít spiking, is there any reason I should do a water change? Should I change some water once a week just to remove the waste at the bottom of the tank (even if my water parameters are ok) or is that just going to encourage algae? Or, is my bioload simply too heavy for such infrequent water changes? How am I supposed to decide how frequently to change the water?
You can dose fleet for phosphates which is what I think you are talking about. Don't get too carried away though. It can cause adverse reactions with plants. A little goes a long way. You might want to dose some potassium for your plants, but I would imagine that your low light setup is probably not too demanding fert wise.
Yes, the fleet is for phosphorous, and the florapride is for potassium. I think Iím going to start by dosing one drop of each with every water change and see how that goes (I usually change 25%, maybe a bit less). Iím guessing that it would probably be easier for me to use dry ferts (since itís easy to find information about how many mgs/tsp of dry ferts to add each week, unlike premade ferts), but Iíd really like to use up the stuff I have before buying more.
One more thing: Homer suggested Excel for a carbon source for your plants. I don't think that he was aware that you had vals. Excel is a good source of carbon for plants albiet it is expensive. There are also some plants that don't do well with Excel. Vals is one of those plants. They tend to melt or just die out.
I suppose itís good that Iím having trouble finding excel, then, lol. None of my LFSs carry it, apparently. If I do find some, though, Iíll probably just get rid of the vals.