I'm going to be purchasing a finnex planted+ 30" light for my 20 gallon long soon and was thinking of moving on up to a bigger tank. I'm torn between a 29 and a 37 gallon tank. Both are 30 inches long and will fit my light and my stand, but I don't know if the light will reach the bottom of the 37. It's 23 inches deep. I plan on carpeting either dwarf tears or dwarf hair grass.
On a 20 gallon long the P+ would be a very strong light, but on the 37 it would be weak. I would advise buying the Finnex Ray II instead because it has quite a bit higher PAR and I think it is only $5 more. But the Ray II would be completely overkill on the 20 gallon. I just happen to have the comparison here because I recent was researching it. @12 inches Finnex FugeRay PAR=45, Cost $83 Finnex FugeRay P+ PAR=61, Cost $93 Finnex Ray 2 PAR=74, Cost $98 The Ray II still has 44 PAR at 24", I don't have the numbers handy for the FugeRay P+. I happen to own all three of these lights btw.
I actually ordered a planted+ for my 20L just the other day. Amazon has it for $87 plus prime shipping, so that's really really nice. I wouldn't try it for the 37, it just wouldn't work for a carpet. One would probably be considered medium light for a 29g, but I'd personally either use two fixtures or go up to a ray 2. Regardless, if you use it for a 20, you're definitely going to need some serious CO2 and ferts. Probably even NKP supplements.
Okay I'll lookat the ray II for sure. And why would I need to dose co2 for it on my 20 long? I don't understand. And would the ray II be sufficient to carpet the 37?
The Ray II has a PAR of 74 on a 20 gallon long, this is really high light, and you would need CO2 and NPK ferts so that the plants can make use of all that light and outcompete the algae. Otherwise you would only have algae, and a lot of it. The same light on a 37 has a PAR of 44 which is medium light (btw. low light ends at 30 PAR). You could grow some of the carpet plants although most carpet plants grow better under high light. Most grow under medium light but grow much taller, like they are stretching toward the light. At the medium area of light, you would be best to have CO2 and NPK ferts, but it is borderline and is usually considered optional at this level. I myself would still dose NPK ferts and at least use liquid carbon (eg Excel) in order to have the best success. In case you don't know what PAR is, it is the amount of light that is usable by plants for photosynthesis, and it decreases with distance from the light fixture, hence the variable number.
Okay I do have liquid carbon. Not excel but it's API brand. And what are NPK frets exactly? Is that like flourish or is it different? And I've also heard that some plants will melt with liquid carbon. My contortion val started to before I stopped using it. And would it be high light on a 29?
NPK are Nitrogen, Phosphate, and Potassium. They're three macronutrients that plants need. In a high light tank (which the 20 would be), the plants tend to suck these up faster than your fish produce them. Thus, people dose them as fertilizers. Remember that the holy trinity of plants is CO2, Light, & Nutrients. If they aren't in balance, you're going to have crazy algae issues, and IMO excess light is the biggest offender. By the way, here's a nice article explaining PAR: http://www.plantedtank.net/forums/showthread.php?t=184368 I think I saw a planted+ par chart the other day... I'll edit if I find it. EDIT: Can't find the par data for anything other than the 24-inch: 3": 185 6": 117 9": 88 12": 61 15": 45 source: http://www.plantedtank.net/forums/showthread.php?t=338114&highlight= For some reason I can't find par values for the 30" ray 2 anywhere. 24" and 36" are easy, but no 30"
Flourish has a small amount of NPK. These terms all mean the same thing: macros = NPK = Nitrogen, Phosphorus, Potassium. You can buy the NPK ferts in a pure form for really cheap, that is why most planted tank enthusiasts eventually go with dry ferts. Popular right now is PPS Pro which is simply a dosing regiment using dry ferts which includes both macros and micro nutrients. Cost $30 here at Greenleaf, but they will last you years. Vals are really the only common plants that just can't handle Excel at all, and even they can get used to it (with limited success), but are real sensitive to starting and stopping it, or erratic dosing regiments. Few other plants will melt if you start or stop using it, but will usually recover (such as hornwort).
Okay well I don't have a huge problem with parting with the val. And I'm also in the process of making root tabs with osmocote plus if that makes a difference with the ferts thing. And so if I'm over-lighting my tank I just need to use excel and not necessarily have a co2 tabk and diffuser right? Or do i need to be doing that?
I have a 75 with an oddysea 48" dual bulb, flourish root tabs, and I dose with leaf zone with water changes. EVERYTHING is growing OUT OF CONTROL! Lol... Amazon swords, jungle Val, melon swords, java moss, java fern. I've never been able to grow anything this fast! Had to cut my lighting back a few hours because of algae, but my mysterys are getting it under control Sent from my iPhone using Fish Lore Aquarium Fish Forum
I think it really does depend which tank you go with. If you go with a 29, excel might do it. In the 20, I would really go with injected co2. In the 37g, don't bother. Root tabs are irrelevant to algae, since they don't generally leak nutrients into the water column so much, and algae doesn't really grow *in* the substrate (sometimes on, though).
Okay so I believe I'll go with the ray II. I'll get some dry ferts to add and I'll probably end up going with the 29. I'll look more into doing pressurized co2 as well. I'm also wanting to look at doing a dirted tank. Anyone have recommendations for soil?
I think you are right to go with the 29 gallon. The extra height of the 37 is not really usable space and wouldn't allow you to add many extra fish. The shorter 29 would make it a lot easier to grow plants. I like Eco-complete, I think it is the most hassle free way to go, while providing all the needed nutrients for the plant roots. Although I still give heavy rooters root tabs as well.
And can anyone find par data for the 30" finnex ray II on a 23" deep tank??? I can't find it anywhere!
Just going off the 24" and 36", I'd guess that you'd be looking at a PAR of around 30-35 at that depth. Taller plants will be fine, but I suspect you won't be getting much of a carpet.
