Fertilizer and Plant questions
I am a new member of ‘The Planted Tank’ but I have been reading the forum for a while now (probably about 6 months off and on). I want to say ‘thank you’ to all of the members and to those who post because I have learned so much by reading different threads. This is really a cool hobby (addictive too) and I hope that I can get my tank to look as good as some of those that I have seen. I have some general questions, but first I want to provide a little background.
I started with my first fish tank EVER about a year ago and very quickly learned (thanks in large part to this site) that I needed to know a lot more if I was going to create a nice looking planted tank. I started off with buying a 30g tank setup from a LFS (aquaclear filter), but quickly realized that my light and substrate were not good enough. So I took the plunge and bought eco-complete substrate and power compact lighting (36 inch, 110W, 9325o GE bulbs) for about 3.6 wpg. I then started injecting CO2 with the DIY method using sugar and yeast, but this got old quickly. I got a 5 lb CO2 tank and Eheim diffuser and it works great. I’ve had this setup for about the past 6 to 9 months. My plants are growing fairly well, but in my opinion, it is just not up to the level of some of the other tanks I have seen. So recently, I have decided to take the next step and start with the fertilizers via the Tom Barr Estimative Index routine based on all of the good things I have read about it (Thanks Tom and others!!). I purchased KNO3, KH2PO4, K2SO4, Plantex CSM+B, Iron Chelate, and MgSO4 from Greg Watson. Also picked up a water-bed drain-fill kit and some tygon tubing for a DIY python……makes those weekly water changes much easier.
So my first question is in regards to whether I have my fertilizing routine correct. The plan is to go with a weekly schedule….
50% water change
dose ¼ tsp. KNO3 for 7.5 ppm NO3
dose 1/16 tsp. KH2PO4 for 1.8 ppm PO4
dose CSM+B, mix 1 tbsp with 250 mL of water for stock solution, does 6 mL at a time
Days 3, 5, and 7 – same as day 1 but without the water change
Days 4&6 – same as day 2
Do I need to add K2SO4, MgSO4, or Iron Chelate? The water quality report for our local area says that there is 18 ppm Mg, 0.126 ppm Fe, but it does not list the amount of K.
- K: I figure that the amount of K from the KNO3 and KH2PO4 is about 5.5 ppm, so I’m guessing that I should add ¼ to ½ tsp. of K2SO4 to add another 6 to 12 ppm of K to bring the total up to the 10-30 ppm level recommended by Tom Barr, assuming none is there initially from the tap. Any thoughts?
- Mg: How about the Mg? I don’t know the recommended level for this and there is some there already from the tap (18 ppm).
- Fe: How about the extra iron from the iron chelate. I have read a post where Tom mentions that the amount of iron in the Plantex CSM+B (7%) is enough and he doesn’t add extra. However I figure that with a stock solution of 1 tbsp CSM+B to 250 mL water, if I add 6 mL to my 30 g (I got this from a number of other posts where it was recommended to dose 10mL in a 50g tank), the estimated iron concentration is 0.25 ppm which is below the recommended value of 0.5 ppm from Tom. So my thoughts are that I should add another 4 mL of the 10% iron chelate stock solution (made the same…1 tbsp to 250 mL of water) to bring up the total value to 0.5 ppm iron, if my math is correct. Thoughts? (caveat: this is based on the assumption that there is about 17 g per tbsp of both the iron chelate and the CSM+B. Chuck Gadd’s calculator gives values for everything but these so I just assumed. It may be off. I need to do the experiment or find someone who knows).
I realize that the answer might be ‘try it and see’, but I am really trying to understand this as much as possible because for some strange reason, I find this all very cool.
Also, I would like some suggestions as to plants…..I currently have corkscrew val, dwarf hairgrass, purple cabomba, rotala indica, java fern, 2 swords, 2 crypts, lace fern, and a few other stem plants. I removed some water sprite and hygro due to how fast it seemed to grow. It always seemed to be growing so big and bushy that it would dwarf the other plants. My understanding is that you start with some fast growing plants to get the tank established and then you can switch to some slower growing ones. Well I think that I am at that point, but I don’t know what to put in. I definitely want to put some riccia in and if anyone has suggestions on the best place to get this, that would be great. I am planning on either tying it to a rock or maybe using some of the stainless steel rod weights that I have seen Buck talk about. I really don’t care too much for the dwarf hairgrass groundcover and want to replace it with glosso, but I have tried to get it to grow in the past, and it has just died out. I’m hoping that now that I am fertilizing, the glosso will grow well. I have pretty much tried most of what my LFS has in stock, but have been wanting to do more, so any input in terms of where to go would be great. Opinions?
Anyway, I hope this post is not too long and I would appreciate any input. Thanks in advance. This is really a great discussion group.