Leaves Are Yellow - Need to Fertilize?

[The_Desacrator]

Howdy Yall. This thread's contents pertain to my two Anubia Nanas in my 37 gal frehswater tank. the tank is about 6 months old, and I recently put the second Anubia a couple of weeks ago. The other I have had since I started the tank. Just recently (in the past 2 weeks) both plants leaves have started to yellow. Also the new (and smaller) anubia has had its leaves chewed on. I perform ~50% water changes weekly.

Another problem, I had 3(now two) Amazon Swords and they are not growing. I have had them since I got the tank started but the leaves only grow to about an inch in a half. When I got them the leaves were 3-4 + inches. All of these are in the same tank.

I also have two new Anbuias in a 10 gallon that I started 4-5 days ago.

Should I fertilize in any of these situations?

 

[mommytron]

some questions: what is your light situation? how many watts? is it a relatively tall tank? are you dosing CO2 or any other kind of fertilizer/supplement?

anubias does not normally need anything but a level of low light to grow. however when you have more than low light over your tank, it may require you to need CO2 and/or other fertilization.

i have low light over my tank and my anubias barteri and anubias nana both do great. i also dose flourish excel once a week with each water change.

 

[The_Desacrator]

I am not using CO2 or any other kind of fertilizer. The lamp on the 10gal says dont go past 25watts, so i am assuing that the 2 bulbs are 25watts. The 37gal hood doesnt say the wattage, but the bulb has 4000k on it.The 37 gal is pretty tall

 

[fort384]

I would look again at lighting. That is more than likely the problem here. A 4000K bulb is pretty much worthless for growing plants. You ideally need about 20-30 watts total over the 10 to grow low light plants, and ideally about 40-50 watts minimum over the 37 to grow low light plants. You could get by with less but this would be ideal. What kind of lights are they that are in the hood? Are they florescent? incandescent? You need bulbs that are in the 6500K-10000K color temp range to effectively grow plants.

 

[The_Desacrator]

The 10 gallon has 2 incandescent bulbs.

The 37 gallon has 1 fluorescent Bulb, this I determined from the attached link.

What wattage/what kind of bulbs should i get to replace the ones I have? Also are any of them fine as is or should I be expected to replace all three?

Types of Light Bulbs

 

[fort384]

For the 10 gal I would look at getting some of those funky spiral shaped CFL bulbs. That would probably be enough for low light plants. The incandescent lights will be almost worthless.

For the 37 gal, what wattage and t size is the bulb? It should say on the bulb itself. If there is confusion, just post all the numbers/what it says on the bulb. I suspect it is probably a 15-20w T8. If this is the case it will be difficult to grow live plants without an upgrade. It might be possible but you will at least need to get a bulb with the proper color temp... 6500K-10000K.

 

[The_Desacrator]

Ok I replaced the bulbs in the 10 gallon with 2 MARINA 25W 120V Aquarium Light bulbs but now the lights are pink +/. So I am gonna go back and get the clear bulbs. Also its barely lit now. With the original bulbs everything was very easy to see and very clear.

For the 37gal I got a GLO Aqua-Glo bul 18000kb. This one gives a weak light blueish tone to the entire tank. I thinmk I am gonna return this one also.

Any comments.

 

[fort384]

What are the K ratings on the bulbs? That will be the determining factor to whether or not the bulbs are putting out light usable to the plants. It has to be between 6500K-10000K. The 18000K bulb will be no good for growing plants.

The MARINA 25W 120V Aquarium Light bulbs, are they compact florescent? Incandescent lights are not going to work very well for growing plants.

 

[The_Desacrator]

So it looks like I am returning the 37 gal one too. Is 6700k enough? Because the next step down is 6700k.

The MARINAs are incandescent. I read online they are supposed to be for reptiles. So I will be returning them.

 

[fort384]

6700K will be great for plants.

Check lowes or home depot for some Compact Florescent bulbs (they fit into an incandescent socket, but are those spiral looking deals). A lot of folks have a lot of success on small tanks with them. I believe the daylight bulbs of that model at 10000K.

 

[The_Desacrator]

Well the hood I have right how only accepts two mini bulbs, but I know a shop that sells 10 gallon lids that have fluorescent bulbs. I will go to home depot tomorrow.

 

[fort384]

ahh ok, that will be even better. Just make sure the bulb you are getting is in that 6500-10000K range... It will probably be a 15W T-8 bulb if it is a single bulb fixture. That would be enough to grow some low light plants.

 

[The_Desacrator]

I got new bulbs for both my tanks, but I still need a fluorescent hood for the 10 gallon.