Half my plants dying?

**zachsta18** · 20th Jan 2012, 03:06 PM

So I have a 75 gallon CRS tank that is heavily planted. I have some fertilizer underneath the gravel (don't worry, there is no copper, and my CRS are quite happy

), plenty of lighting, and a CO2 injection system. The plants are symmetrical, with a wide variety of plants, but one half of the tank seems to be dying. I thought the problem might be that the CO2 was being pushed to the other side of the tank by a sponge filter I have running in the tank to move water around, so I added another CO2 injection system on the side of the dying plants just a few hours ago, hoping it would solve the problem. I know CO2 injection can be a problem with suffocating shrimp, but I have a 30 inch bubble bar in the back, and good tank circulation, so I should be good, right? I just want my plants to be healthy and happy, and same goes for my CRS, without either of them dying. It seems to be a very delicate balance. But do you think the problem was just the CO2, or could it be something else? I also don't want the plants to suddenly die and create ammonia and kill my shrimp

And the plants are the exact same plants, in the same arrangement on both sides ( I got a little OCD with my plant configuration...).
Thanks in advance for all your help!
~Zach

**Bratyboy2** · 20th Jan 2012, 05:11 PM

the plants are not getting what they need. Do you dose ferts? Do you only do it to the healthy side?

Are these brand new plants that you just got that could be acclimating faster then the others?

What are the plants? Crypts go through a melt if you mess with them.

**zachsta18** · 21st Jan 2012, 09:04 AM

No, I don't dose ferts, there is a fertilizer under my gravel substrate. The plants have been in my tank for around 3 weeks so far, but unfortunately I don't know the type of plants because I bought them at an LFS here in Singapore which sells them 3 for $2.50. They are quite assorted in my tank, and the same plants on each side mirrored, just one side is dying, one is not.... it's strange... but thanks for the info! I'll look into the species of the plants...

**retardo** · 21st Jan 2012, 09:28 PM

Your plants are dying from lack of nutrients. In addition to carbon (from CO2), your plants require NPK (Nitrogen, Phosphorus, Potassium) and micronutrients to grow. If it is lacking in NPK, it will show signs of yellowing and holes in leaves, stunted growth, etc. It's unclear what fertilizers you have in the substrate but it's clearly not enough. Because you are injecting CO2 which is forcing the plants to grow, but without its counterparts (NPK and micros), the plants simply do not have what they need. I'd considering buying some liquid (or dry) fertilizers to supplement what you are doing.

There's also the consideration of light quality. What kind of light are you running? Higher light means your plants want to grow faster but again without ferts to promote growth, your plants will not make it.

**zachsta18** · 22nd Jan 2012, 07:39 AM

Thanks for the help! I think that the fertilizer I put under the gravel (about an inch thick) might be too far under the gravel, or too thinned out on the side with the dying plants, so I might pull the plants out and mess with the gravel/fertilizer to see if I can get the gravel a little lower, and a little more fertilizer on that side. As far as lights go, I have a 4 foot light running 4 36W fluorescent bulbs. So should I put in liquid ferts on the dying side, and not the side that is healthy, so that the ferts are directed at the dying plants? Thanks again!
~Zach

**retardo** · 24th Jan 2012, 07:03 PM

Aquatic plants take up nutrients through two primary means--through the roots and from the water column directly. Some plants (such as crypts or swords) are heavy root feeders and will have extensive root systems for anchoring and nutrient collection. Others (i.e., those with shallow root systems) rely more heavily on collecting nutrients primarily through the leaves. Regardless of whether you use dry or liquid ferts, the ferts will dilute in the water and be made available to all the plants. That is, if you squirt liquid ferts into one end of the tank, it will eventually dilute until the injected liquid has a equal consistency throughout (equilibrium through osmosis). You can target specific plants (i.e., root feeders) by supplementing with root tabs and make more nutrients more directly available and cause the plants to grow faster.

All that said, I don't think it's necessary to mess with your substrate. Just figure out a good consistent fertilizing method and stick to it. Many of us in the states employ the Estimative Index (EI) method. For more info, go here. HTH

**Hwynette** · 24th Jan 2012, 11:10 PM

Originally Posted by retardo

Aquatic plants take up nutrients through two primary means--through the roots and from the water column directly. Some plants (such as crypts or swords) are heavy root feeders and will have extensive root systems for anchoring and nutrient collection. Others (i.e., those with shallow root systems) rely more heavily on collecting nutrients primarily through the leaves. Regardless of whether you use dry or liquid ferts, the ferts will dilute in the water and be made available to all the plants. That is, if you squirt liquid ferts into one end of the tank, it will eventually dilute until the injected liquid has a equal consistency throughout (equilibrium through osmosis). You can target specific plants (i.e., root feeders) by supplementing with root tabs and make more nutrients more directly available and cause the plants to grow faster.

All that said, I don't think it's necessary to mess with your substrate. Just figure out a good consistent fertilizing method and stick to it. Many of us in the states employ the Estimative Index (EI) method. For more info, go here. HTH

I read the article by Barr. Sad to say, a little over my head. I have very few plants in my 29 gal but they don't look too great. Some are yellowing, others are losing leaves/branches/bits. They are just stems in the gravel; no nutritive soil. I've just started adding Flourish. Excel and Iron (no shrimp in this tank). I don't have C02, but some pretty good LED lights (blue/white). I don't want to bother trying to dose etc if my set up isn't going to work with no C02? Can you have plants without all this dosing or no? Any super hardy plants that can do okay on their own? Thanks in advance.

**retardo** · 25th Jan 2012, 09:10 PM

EI is pretty simple. The basic premise is to provide an excess of nutrients in the water column such that the nutrients are readily available when plants need them, eliminating possible deficiencies. Water changes are done weekly to "reset" the water back to normal conditions.

Is EI and fertilization necessary? Not necessarily. I actually am keeping a 20G shrimp tank that houses CRS and yellow shrimp without a filter and only has a heater. I top off the tank using WC water from my EI-dosed tank, so the plants are getting some nutrients. There is no CO2 injection. I have also kept a 10G tank that I only topped off with tap water, no ferts and plants grew perfectly fine, albeit a lot slower.

**Hwynette** · 26th Jan 2012, 11:09 AM

That's interesting, thank you. What type of plants do you have in your tanks?

**CTale** · 26th Jan 2012, 12:24 PM

You should check some basic things:

- light coverage (is it same for both healthy and other side)
- even water flow (distribution of nutrition matter and CO2)
- if the plants were grown under or out of the water before you bought them (if they were above the water they should ditch old leaves and start to grow new ones)