NH4 spike suppression

[scottward]

Hi guys,

Am I correct in thinking that the current accepted theory regarding algal germination is that algal spores 'float' about in a tank, an ammonia spike occurs (i.e. some level of ammonia greater than what the bacteria in the filter/tank is currently accustomed to; hence they don't fully 'supress' it), the algal spores germinate...?

This event that creates the NH4 spike might be something like a failing solenoid, blocked bubble counter etc, causing a drop in CO2 levels in the tank, which in turn causes the plants to expend some time/energy manipulating Rubisco levels instead of regular NH4 harvesting - hence the slight spike in NH4?

I know that, for example, Zeolite, is used during tank start up (whilst bacteria levels are building up to handle it).

Is it beneficial to put some Zeolite in the system somewhere as a 'safety net' should an unexpected event like a solenoid failure etc occur? That way, should a NH4 spike occur, I would assume that the Zeolite, provided sufficient water turnover through it, could mop up the spike before the algal spores get a chance to use it as a 'signal' to germinate?

Or is this idea flawed simply because:
- the algal spores will respond much faster than the Zeolite
- the Zeolite would need far too much maintenance to keep it in a useful state; over time it would simply clog with bacteria thereby rendering it unable to capture NH4 spikes
- the Zeolite wouldn't 'selectively' capture the NH4 spikes; it would constantly capture 'ambient' low levels of ammonia (i.e. from the fishes gills) such that it would need constant recharging

Just wondering.

I think I can see why Tom suggest's lots of water changes, good filter maintenance etc - keep the algal spore concentration as low as possible in the first place!

If I also recall correctly, the concept of using UV won't work either because the light wavelength isn't sufficent to kill off the common problematic algae species?

Scott.

 

[1077]

Interesting thoughts. Can't help but think plant's would consume ammonia spike quite quickly unless it was chronic condition over extended period.
If plant mass was not large enough,then perhaps algae would quickly take advantage.
I have low tech,low light, NonCO2 heavily stocked and heavily planted and other than diatoms at initial set up last July, have seen zero algae (well maybe some thread algae on tips of tall growing plant's). No solenoid or bubble counter to clog and am near certain that NH4 levels fluctuate slightly such as after feedings,or with addition of new fauna.

 

[Hallen]

I do not fully agree, there are many species of algae which appear under different conditions so you can't say algae in general germinatie when NH4 is high enough. If NH4 should be the cause of a certain species of algae to germinate it's easy to test. Add some extra NH4 in a fishless tank and see what happens. If NH4 is really the cause of algae you should be able to trigger them at a certain level and induce the same species everytime you do it.

Some questions do pop in mind if it's true that NH4 triggers certain algae species to germinate. Why Nh4? Because it's easier in terms of uptake? - Bad plantgrowth can't be the cause either, since they still have a source of N. Perhaps the switching between two different sources of N has an affect on plantgrowth, which in turn triggers algae to germinate? I don't know

I never use stuff like Zeolite imho it's rubbish for planted tanks, it hogs up Po4 and No3. Especially planted tanks don't need fancy filter materials, plants themselfs and your substrate do that job quite well. Also if there's an excess plants will use up the NH4 quite fast, they prefer this form of N over No3, as 1077 already mentioned aswell.

 

[Tom Barr]

If the plant is limited by P or CO2..........then the ability to take up and process NH4 is severely reduced. There are some good papers on this using Stratiotes Smolders et al, 1996

A large water change + dosing resolves most of that, but not CO2.

Zeolite is not bad per se.........I view it as sometime to start a new tank with, and as something that can be loaded with nutrients for plant roots, but mostly..........as a bacterial substrate/media. This is what it's often used for IME.
some folks have added it to their sediment, like pumic or like ADA PS.
I see little issues with using it, it's light weight and I hate mixing sediment types.

For the filter perhaps as biomedia.
Also, I think ti is EXTREMELY important to include a concentration of NH4 when discussing algae and I think there's a few other factor sinvolved, NH4 byitself at moderate/low levels, say 1ppm or less, should not be an issue.

If we look at ADA AS in new tanks...the NH4 goes way beyond 1ppm........but there is a lot of peat and tannins.......diatoms are common, but not the green and BBA etc.
This might be due to tannins and pH.

Still, NH4 by itself as a lone inducer........has been falsified. I'm not going to argue the lost cause.
It might induce under some conditions and is not good for shrimp and fish, and high levels can toast plants.

Under higher light, poor CO2.......NH4 seems to cause mayhem........but high light and poor CO2 cause mayhem by themselves just fine as well.
Without quantifying this additional effect, I cannot say much and can only speculate.
From ADA AS.......pH/tannins also play a role it seems.

Maybe the lowering of O2 from sediment disturbance, or simply too much plant/root/bacterial disturbance is more what causes issues.

I only noted Green water and perhaps secondarily, Staghorn.........maybe BBA at the end.
This was done by progressively over loading the fish population with creek chub minnows.

So a drain in O2, over loading the filter, high light etc.........but good current and open plant layout with fast growing weeds.....
I think fish produced waste etc.......vs say NH4 from fertilizers like KNO3 vs N from fish waste are different.

It's not a simple thing.

 

[scottward]

Thanks for the reply guys.

Scott.