Injected CO2 + EI Dosing + Good Flow = No Growth?!

[jagillham]

Starting to tear my hair out here with the lack of progress with my tank. I *feel* like I'm doing everything right, but not having the lush green growth others enjoy.

So here is the spec...

Tank: 122cm (4ft) Long x 60cm (2ft) Tall x 50cm (19") Wide
Dosing 90ml EI (standard mix) daily & carrying out 50% water change weekly.
CO2 - Drop checker kept green
Light - 3x 54w T5's with reflectors
Filtration via sump with Eheim Compact 3000 return pump & 3000lph powerhead
Sand over Verve Aquatic Compost (B&Q)

The EI I have been running since April / May 2015. The compost base was added 21st November.

Here is the tank Nov 2015...



And here it is today...



As you can see. No growth in the MC or the Japonica Blyxa. Amazon sword atleast seems to be doing something.

Drop checker is green. pH test today is showing 6.8pH. I think one issue my lay in the fact the KH is 14 degrees. If I read the charts right, that's too much CO2?

You can see the positioning of the powerhead, and below is a closer shot of the filter return up the top with the CO2 rising into its path.



Any ideas or advise appreciated. 🙂

 

[Ryan Thang To]

i would say that glass diffuser is not big enough. try a reactor or a bigger glass diffuser. i have my co2 pump straight into the external filter work brilliant.

cheers
ryan

 

[PARAGUAY]

If you have another drop checker place it in another part of tank to check readings are consistent and flow around the aquarium is ok.Lighting you could try reducing it a little in the short term and when plant growth improves ramp it up gradually to suit.Could it be the lighting is too high to early it which case increase the amount of EI slowly as lack of enough nutrients could well be an issue, still using the alternate regime.Plants like Amazons actually take kindly to a trim I've found so remove any poor or dead or damaged leaves.You could place some fast growing stems as a temporary measure at the back

 

[jagillham]

The CO2 levels would appear to be OK according to the drop checker / pH vs KH chart?

I did remove around a dozen melted Sword leaves. I'm not sure if that was the move or something else that did that. I do however have what looks like green spot algae on the remaining leaves.

The extra light was added around the same time as the soil base. I had the feeling that the height of tank meant low light at the base, leading to my foreground plants doing not much.

There looks to be decent flow along the substrate as all the plants moving. I've tried having the power head lower before, but it just ended up shifting the sand to one end of the tank over time.

How slowly would you introduce more EI mix, and to what kind of dose? Isn't MC supposed to grow great under any conditions, not sure why mine not taken hold.

 

[foxfish]

I cant see how you main pump returns?
I would remove the 'in tank diffuser' & place it in front of your return pump.
That alone will really improve your C02 distribution, then measure the PH drop because I suspect you simply don't have enough C02 to get lush fast growth.
From my personal experience you are going to need lots of gas in a tank that size!
I have found this an easy way to get the co2 into the sump pump using a cut down plastic bottle.....

 

[rebel]

Dude, at high kh, you can run into problems with co2. I think you need to work on dissolving more or getting that kh down.

If you don't have RO, then you can reduce kh by adding vinegar or other strong acid (careful though).

Tom Barr has previously commented on this.

 

[PARAGUAY]

I would gradually increase EI over a few days,reduce the lighting or raise it,appreciate you have a deep tank but they are t5 and as soon as healthy growth appears it's less of a issue and could be increased if you feel the substrate growth would benefit,definetley put some fast growers at the back, in my 3ft I am dosing at least one and half times dosage rate of El all the easy plant category.

 

[jagillham]

I cant see how you main pump returns?

The last picture up the top of it, half behind the CO2 pipe. The return pipe goes up through the base of the overflow box, then out of the side of it as pictured. This is then heading in the direction of the powerhead, so hopefully a nice cyclical motion around the tank.

According to the KH vs pH chart I'm already in the yellow zone for CO2 in the water (14 KH vs 6.8 pH), and since increasing it the Rummy Nose Tetras are staying lower and breathing quicker. Don't think they enjoying it at all.

 

[jagillham]

I've decided to double up on the powerheads, so have brought another 2500lph (same make / model).

Plan being run this alongside the current one. I'll aim the current one a little higher for more surface agitation. The second one I'll have facing the same way 2/3 the way down the tank. Pointing near enough horizontally to encourage flow over the low laying plants.

I've also purchased a cheap PH pen for some hopefully clearer results. I struggle making out the levels on the API colour charts!

Will increase the EI to 150% dose and see how things go 🙂

If I get a chance I'll try to sort some kind of stand so the CO2 is injected into the sump and the bubbles go into the return pump!

 

[Chris Jackson]

I on the other hand suggest you ½ EI there is no way that level of planting needs 150% you can have too much of a good thing particularly traces

 

[jagillham]

And there was me thinking there would be a consensus!

If not the EI, what would you think is the limiting factor?

Can't see how I can add more co2 as fish seem to struggle when it higher and chart shows I'm above 30ppm.

 

[Chris Jackson]

Consensus...hehe

Well I'd explore along the lines of what haven't you tried. The thing that leaps out for me is the high KH and there is something like a consensus that suggests that things are, at the very least, harder with hard water. Can you add rainwater or perhaps get an RO unit?

You should not need fish gasping levels of CO2 with those plants at your light levels and certainly not excessive ferts.

 

[Bacms]

Don't rely on the chart it is known to be incorrect. In a plant tank there are many factors contributing to acidifying the water which aren't unrelated to CO2 content. As others have mentioned you simply must not have enough CO2. You provide the pH value but not how much it drops when injecting CO2. Green drop checker needs to be lime green not dark green

Sent from my GT-I9505 using Tapatalk

 

[jagillham]

I'm not convinced on my results to be fair. Supposedly with my KH and pH I'm running at CO2 in the region of 70ppm.

I did look into the high KH aspect, very little in the way of agreement about the effect in a planted tank.

There is a lot of hard water areas in the UK, I'd be surprised if there was such a relationship. Otherwise most of the South East would be on here with troubles?

 

[jagillham]

To answer the above, my pH prior to all this CO2 injecting malarkey is around 8.4 after allowing gassing off.

 

[Bacms]

Yes the KH relationship with the CO2 injecting is thought to be mainly irrelevant since the carbonate equilibrium only accounts for a small proportion of the CO2 dissolved in the water and so can be safely ignored. At least that is the view of most people.

How are you measuring that 8.4? it does seem a quite high pH value?

I am in Cambridge with hard water similar to yours and didn't have problems with CO2 injection. I was also at high levels of CO2 and my pH would be around 6.4 before I added livestock. Once that was added I had to reduce to much safer levels. I am now on pH 8 without CO2 to 6.8 at lights on.

 

[jagillham]

Would seem high, but not surprising given my area. I'm awaiting a pH pen as the API tests are a struggle to see the colours. Especially when the PH is somewhere between the high and low test.

Here is some I took a while back. Ignore the ones on the far left. The middle one is water that has been allowed to "gas off", and the right one is straight from the tap...

pH low range


pH high range


Local water is 7.3 pH according to Southern Water for my postcode. Which is about what my "straight from tap" API test result says.

 

[ian_m]

You can't really use these test kits, other than to empty your wallet. As you have found you will get inconsistent results due to other ions interfering with the reagents, especially if you are testing tank water. I suspect something else in your water is causing the mismatch between pH high and low ranges.

Presence of chloride is known to make tests produce erroneous results along with dechlorinator in from tank water.

 

[Bacms]

Yes if you are measuring your pH with the test kits I wouldn't worry too much. I would wait until you have the pH pen and then measure everything again. Specially with the high and low ranges of pH I often foun I could made up a reading just by using the wrong kit. Since you are not having melting or anything just slow grow just wait for the pen

 

[jagillham]

pH pen arrived, just need to get it calibrated.

Second 2500lph power head is in though 🙂



The Monte Carlo is starting to take now which is good news!