40 gallon planted tank struggling

[Consultree]

I have a 40 gallon planted tank with several types of plants. I have two 36W-6700K bulbs.the plants grow but don't thrive. Any suggestions to what fertilizers might help?

 

[BBradbury]

Your 40 G

I have a 40 gallon planted tank with several types of plants. I have two 36W-6700K bulbs.the plants grow but don't thrive. Any suggestions to what fertilizers might help?

Hello Con...

If your plants haven't been in the tank long, then they need time to get used to your water conditions.

A variety of plants will likely have different lighting needs. Review their requirements to make sure you're providing what's needed. Plants need a variety of spectrum lighting like they need a variety of nutrients. I have a two light strip. One is 6700K and the other 10,000K. This has worked well.

My planted tanks are heavily stocked with fish, so I just feed a balanced diet and change out a lot of tank water regularly and don't use much in the way of commercial fertilizers. I understand Seachem has a good product, you might start there if you feel your plants aren't getting all the nutrients they need.

B

 

[Old Scales]

You've got good lights for plants. But with more light you also need ferts and a source of carbon. Research ferts for macros as well as micro nutrients. For a 40g I reccomend going with dry ferts. Check out Green Leaf Aquarium's PPS-pro or EI fert system. MUCH cheaper than liquid ferts and more complete. You definitely need a source of carbon as atmospheric CO2 is only enough for the most low light, slowest growing types of planrs. You need to research pressurized or DIY CO2 and look at liquid carbon such as Excel or much cheaper Metricyde 14 (Gluteraldyhide) from Amazon.com.
Read alot of the old post in the planted tank section and WELCOME to AA. Good site with great people! OS.

 

[Catfish Lover]

I have a 40 gallon planted tank with several types of plants. I have two 36W-6700K bulbs.the plants grow but don't thrive. Any suggestions to what fertilizers might help?

I use and most people here would suggest seachem flourish liquid and the root tabs if you have root feeding plants. Is this T5 or T8 lighting? If I had to guess from looking at the wattage I'd say T8. If it is T8 I'd dose twice a week. How long have you had the plants? This would be a low light and the plants won't grow a foot in a week.
, it takes some time, just be patient.

 

[Consultree]

Not sure if it's either. Here is a pic of the lights

 

[Consultree]

These are my plants:
Red melon sword
Cryptocoryne wendtii-red
European clover
Valisneria
Hygrophila pinnatafida- Indian swamp weed

 

[tiger terror]

Not sure if it's either. Here is a pic of the lights

Those look to be power compacts..

 

[Rivercats]

Using a liquid fert with that light is not only going to cost a lot but it won't provide the plants with the proper macro and micro nutrients needed.

You can get a gallon of Metricide 14 Day Solution for around $27 shipped but do shop around online as some places try charging up to $40 a gallon which is way too high. It is then mixed at a 1:1 ratio with RO or distilled water to get 2 gallons for under $30. You can't beat that price, just check out how much Excel would cost for that much. Then with the lighting you have you would start with 1ml Glut (Metricide 14) for every 5 gallons of tank water. In about 2-3 weeks you want to up your Glut dosage to 1ml per ever 2 gallons of tank water.

For dry ferts all you need is this $15 package... Estimative Index | Aquarium Fertilizer | Green Leaf Aquariums.

You will also need 3 dosing bottles (look at the bottom of this page)... Aquarium Plant Fertilizer | Green Leaf Aquariums.

Here is a good article about dosing PPS-Pro and the recipe for the amounts of dry ferts to mix in which you will also need a gram scale. Only read the opening post not all the comments afterwards... Newbie Guide to PPS-Pro - PPS Analysis and Feedback - Aquatic Plant Central.

You will notice I do two things different than the article. First I use 3 dosing bottles instead of 2 because I separate and mix nitrates in one bottle, potassium and phosphates in another bottle, then micro's in the 3rd bottle. This allow for better custom dosing in your tank. You'll also notice the recipe amounts call for MgSO4, magnesium sulfate, which if you have hard tap water with a Kh and Gh of at least 3 or 4 you don't need to use this.

With your lighting if you use these ferts and the proper amount of liquid carbon (Glut) you'll have a very successful tank. Just be sure not to run lights too long each day or algae can become a problem.