When to start fertilizing?

[Watcher]

I am setting up a 75 gallon, pressurized CO2, 260 watts, flourite substrate(4"), and will be using the EI method.

First time with plants. I've never even touched an aquatic plant yet. And I've been a member here for around 9 months, go figure.

I have read that it will take a couple weeks for the plants to get established. I'm putting in 50+ plants from the offset and believe that I need to dose with CO2 and use lights of course, from day one. But that I should hold off on the fertilizer for 1-4 weeks. If I use fertilizer before the plants need it, it will encourage algae growth.

Is this correct?

 

[VaughnH]

Re: When to start fertilizing?

As soon as you plant aquatic plants they are trying to grow. At least that is what I see. They may not grow vigorously immediately, but they do grow. So, like any other plant, they need NPK and Carbon. That tells me I should begin fertilizing immediately, with all macros and micros as well as CO2. If there are enough fast growing plants from the start the "food" demand of those plants will be met, with little excess, and algae shouldn't be able to start growing.

In my case, I didn't get my CO2 tank until a week after I planted, and then a little cory snuck behind my moss wall where it became a NH4 source. So, I do have algae started. It isn't doing really well yet, but I suspect it soon will - being a pessimist.

 

[Tom Barr]

Re: When to start fertilizing?

You do not need to dose as much, but dosing excesses is not why you have algae.

Try adding some mulm to the bottom layer and to the filter when you start the tank.

You can use mulm from any tank, it's the dirt in the songe filters, or the settled dirt in a vacuumed water change bucket, brown, wet gooey stuff.

That is pure bacteria and a little organic matter.

That is all that is missing from a new tank's gravel.
So add a little bit.

Now your tank is cycled.
No wait, no worry.

Also, add as many plants(even cheapy plants till the others fill in) from the first day.That is the most common mistake new and old folks alike make when doing a new tank.

Substrates do take a little more time till they settle in and do well.

Plant roots quickly grow back out as a rule also, but they need nutrients to do this. So established root systems can help, but we can prune weekly and remove these same roots without any ill effects(but you need to do the water changes asap right afterwards).

So new tanks need: mulm, lots of plants, and lots of water changes for the first 4-8 weeks.

Good CO2, good fert dosing(you can add about 1/2 the macros initially for the first week), etc will help.

Once the tankj settles in, then you will be good.
Attack any and all algae asap(don't wait, a small problem is less work than a big one). Add amano shrimp after a few days etc.

It takes more work to whip a tank into shape, there is no avoiding that, but then once settled in, we can be a bit more lazy.

Regards,
Tom Barr

 

[Watcher]

Re: When to start fertilizing?

You can use mulm from any tank, it's the dirt in the songe filters, or the settled dirt in a vacuumed water change bucket, brown, wet gooey stuff.

Tom, I'm used to doing this for my FO tanks. I plan on not adding fish to my planted tank until I have the plants well established and everything going good.

Is there a benefit to the plants for adding mulm?

Plant roots quickly grow back out as a rule also, but they need nutrients to do this. So established root systems can help, but we can prune weekly and remove these same roots without any ill effects(but you need to do the water changes asap right afterwards).

Do you mean pruning roots weekly? If so in what scenario would someone need to do so? And why is the water change necessary right after? To clean out any suspended debris from the substrate?

Thanks!

 

[Tom Barr]

Re: When to start fertilizing?

I pull up plants and cut the tops off and replant only the tops.
Some folks top the plants and leave the stumps to branch out.
I rarely do that.

The mulm cycles the tank instantly, does not matter what type of tank it is.
Plants are helped by having a NH4 processing/cycling back up, the bacteria and this also provided other plant detritus and other fish waste a means to be decomposed without waiting long for the bacteria to do it's job.

Regards,
Tom Barr

 

[VaughnH]

Re: When to start fertilizing?

Isn't the water change immediately after pulling up plants because you are introducing lots of stuff that was in the substrate into the water column, possibly including NH4? The biggest algae blooms I have had came after pulling out plants when I was using root tabs.

 

[Tom Barr]

Re: When to start fertilizing?

Yes, but there is yet another reason to do a water change.

Low O2.

It might be less due to NH4, and more to do with low O2 from pulling up reduce ions like Fe2+, NH4+, etc, reduce organic matter, all this material is pulled up and rapidly removes the O2 both chemically and biologically.

That is a possible signal for algae I postulate.

I've noted that high O2 does not inhibit algae at all.
Nor does high CO2 and neither induces algae at ambient.

But I have not investigated low O2, we get low CO2 from plant uptake, not an issue but low O2 is quite another matter.

I can remove the O2 by bubbling N2 gas into the water and deoxygenate it.
But this is a no fish/critter tank for sure.

I'm not saying that low O2 is the cause of all algae, it might be a contributor, it also might cause certain species to grow, but NH4 definitely is a causitive agent for algae at relatively low levels.

Regards,
Tom Barr

 

[Watcher]

Re: When to start fertilizing?

This is good stuff. I'm getting interested now.

I've noted that high O2 does not inhibit algae at all.
Nor does high CO2 and neither induces algae at ambient.

This phrase seems to contradict what I thought I understood from the EI write up. Do you mean from above that high CO2 does not inhibit algae? Also do you mean by saying in the first sentence that high O2 does not inhibit nor does high CO2; and also neither induces algae, that levels of O2 and CO2 (whether high or low) are not a factor in algae growth?

From the EI article
It will not cause algae unless you over look something, namely CO2 or under dosing KNO3 which both of these account for about 95% of all algae issues.

Would you clarify why *underdosing or "over look" CO2 causes algae issues? Or did I completely miss your point?

*(I thought you meant underdosing CO2 in the EI article since you mentioned the same percentage of people underdosed CO2, in your opinion, earlier in the same article)

Thanks!

 

[Watcher]

Re: When to start fertilizing?

Tom? I'm a little anxious to hear your thoughts.

 

[Tom Barr]

Re: When to start fertilizing?

This phrase seems to contradict what I thought I understood from the EI write up. Do you mean from above that high CO2 does not inhibit algae? Also do you mean by saying in the first sentence that high O2 does not inhibit nor does high CO2; and also neither induces algae, that levels of O2 and CO2 (whether high or low) are not a factor in algae growth?

Yes, high CO2 do not inhibit algae growth by itself.
Algae, like plants, grow better at high CO2, but the plants grow much better as their needs and uptake is different.

Would you clarify why *underdosing or "over look" CO2 causes algae issues? Or did I completely miss your point?

Sure, it confuses the plant, they adapt to a stable level of CO2, if it's all over, they have trouble, algae much less so.


Regards,
Tom Barr