No Plant Growth

[giganova]

Hi all --

I set up a tank a few months ago and things are working out OK, but not as good as expected.

Overall, the plant growth has stopped after a few weeks and nothing seems to be growing anymore, except american pond weed (growing like crazy) and lots of black hair algae. The other plants are surviving, though, but don't grow.

Its a 29 gallon tank with tons of light (4.5 watt/gallon, 130 watt total), regular gravel, Co2 injection, root tabs for the amazons and some additional fertilizer every few weeks. Lots of fish which are all in excellent health. Ph level is a bit high (7.8) but amonia and nitrates are good. Picture is below.

What do you think keeps the plants from growing? Clearly, something must be missing or wrong, but I can't figure it out!

Thanks!

 

[themissingelf]

The brighter the light the more CO2 and ferts you will need. The light almost forces the plants to grow quicky, therefore, I suspect that your CO2 and ferts are getting used up. Also... do you have plant specific substrate? Essential for good plant growth - particularly at the light levels you specify.

Your high PH suggests a shortage of CO2.

You could try lowering the light levels to about 2wpg

or...

Increasing the ferts and CO2 (although keep testing PH and make sure you turn it off at night).

 

[giganova]

Thanks for your reply!

The Co2 kit that I bought (Nutrafin) doesn't allow to adjust the amount of Co2 injection. I can see maybe 1-2 bubbles per minute or so. I read before that Co2 should decrease the Ph level, but it didn't in my case. the Ph level is exactly the same brfore or after I installed the Co2 injection.

I don't have special substrate, jusr regular gravel, but have put root tabs in almost every plant.

Cheers

 

[Fwapp]

Ermm... Is that an air curtain/stone at the back of the tank? If it is, then that will be driving all of the CO2 out of the water. Remove any air pumps feeding into the tank, and reduce the amount of surface agitation from filter outlets as much as possible. This will allow the CO2 to 'stay' in the water, allowing the plants to utilise it.

If it's not an air curtain/stone, then just ignore me as a raving imbecile !

Hope this is of some help!

 

[mattb]

1-2 bubbles a minute is not what you should expect from a nutrafin unit. I got mine today and used the diy mix and i am at around 25 bubbles a minute after 5 or so hours. Try the link in the co2 thread.

You might also want to stop using the air stone because that will drive off any co2 you have in the water anyway.

 

[giganova]

Indeed, Fwapp -- it is a big air curtain. The Co2 injection in on the right.

I will switch the air off to allow the Co2 to get into the water. Will there be enough air for the fish without air curtain? I have an AquaClear 50 water filter which should provide enough air, correct?

 

[Fwapp]

I have no air stone in my tank, and the surface has minimal disturbance, and even through the hot weather, I had no problems with fish gasping. I do know what you mean though, I was very nervous initially! Try turning off the air on a day when you'll be around to over-see things, that should help boost your confidence in what your doing.

As for your filter, I dont know, as i'm not familiar with it, I'm afraid.

Also what Mattb says about 25 bubbles a minute is quite true. I also have the nutrafin unit, and get a similar rate.

Have a read of the sticky regarding EI dosing. Once you get your head around it, it makes a lot of sense, and your plants will grow amazingly well. Have a look at some of the tank journals (George Farmer, Jimbooo, craynerd, oldwhitewoods and a load of other quality tanks) for examples.

 

[giganova]

That's great info, guys!

I just turned all air stones off and replaced the Nutrafin activator pack (boy does that stink when you open the container!!). When I first got it, about two weeks ago, I used brown sugar instead of white sugar. Maybe that makes a difference. I should see in a few hours if the bubble rate increases.

 

[JamesC]

As previously said CO2 is your main problem. With that amount of light you are going to need to get a lot more in your tank. To give you an idea on my 46 UK gallon tank I have 2-3 bubbles of CO2 per second and I'm running 3wpg of lighting. Remember that 40% plus of plant mass is Carbon so this is what you are going to need most of. I also suggest you start adding fertilisers on a much more regular basis. Have you read this sticky Zig's Estimative Index Article at the top of this section. This will provide you with a lot of info. Also I detail what I do with my tank on my webpage - link in signature.

Reason plants do well for the first couple of weeks is because they have a nutrient store which they are able to call upon. Once this is depleted they stop growing.

Black hair algae AKA Black Brush Algae is a sure sign of CO2 problems. Ubtil your CO2 and dosing is sorted I'd really recommend you half your lighting.

 

[giganova]

Well, I changed the shugar/warm water/activitation(yeast)/stabilization pack in the Co2 injection system about 6 hrs ago and I still only get 1 bubble per minute. Strange.

Why does it not produce more bubbles??

 

[RadaR]

More yeast=more CO2 but runs out quicker. Less yeast=less CO2 but lasts longer.

 

[dasmall1]

Have you tried making a DIY mix? I couldn't tell you exactly how much of everything to add to the nutrafin container since I use pop bottles. You just need sugar, water, and yeast. The nutrafin stuff doesn't work very well or very long.

 

[giganova]

Have you tried making a DIY mix?

I just did an hour ago -- and YES, it works! I had three unsuccessful attempts with the Nutrafin refill packs, which only gave one bubble per minute (what a rip off, I wasted $10.- on these refills!).

With my DIY 1 tbl spoon yeast+1 cup sugar+2.5 cups warm water I am up to 1.2 bubbles per second, which should be OK, I guess, for my 29 gallon tank.

Let's see and wait what happens to the plants over the next few weeks