A Few Issues - Co2, Ferts, Flow & Algae

[David J]

Hi

I have a few issues and questions about my set up.

My tank has been running for 2 years. Up until now it has not had Co2. It has always had live plants (swords, crypts, cabomba, anubias) and has bogwood and a few rocks with part sand part gravel substrate. Up until now I've been dosing neutro T daily.

My issues and questions are:

- Algae

I previously had bad BGA but haven't seen any for a couple of months now after a long battle with it. A few weeks after the last sighting of BGA, brush algae started to appear. It has got slowly worse and now covers about 50% of the light facing top of the bogwood and is quite thick on a couple of rocks. It is on the heater cover also and had secured itself along the full outer edges of much of the plants in the tank. I had to clear out quite a lot and now only had a small amount on a couple of crypts.

I use 2 daylight arcadia Eco aqua led's that are 9w each.

I know fluctuating or low co2 can cause this algae so I'm hoping the introduction of co2 will sort it but does anyone have any advice or observations based on what I've said?

- Flow

I run a Fluval external 206 with a spraybar. (780lph). About 2 months ago I introduced a power head to eradicate dead spots and to help conquer the BGA. I use the Fluval Sea CP2 (1600lph). My tank is 90l so recommended flow rate x10 = 900 and I'm turning over nearly 2400lph.

That much flow has to be bad, right? The spraybar points left to right pointing Dow 45 degrees (over large planted area) and the power head is on the top right side pointing left but upwards creating some water agitation. That angle will of course be reducing the flow but I don't know how much. The flow goes over to the left wall and down, moving sand a lot in the back left corner.

There are no dead spots in the tank. I'm just worried that it's too much flow. The fish are fine with the flow. The CP2 says it's for tanks upto 100L. The smaller CP1 said upto 60L so I feel I bought the right one based on the box but it seems too much.

- Ferts

I have read about the need for micro and macros required in a high tech set up. Today I purchased JBL Ferropol 24 (2 drops daily) and JBL Proscape NPK Macro-elements(5ml daily).

Has anyone used these products? Should I be using anything else in addition to those. Root tabs?

-Co2

Starting with my first pressurised co2 kit today and building up to 30ppm over the next few days. I have the diffuser in the bottom left rear corner about 7 or 8 inches from the filter intake. I'd say roughly 20% of the bubbles enter the intake. Is this going to be an issue or does it just come out of spraybar?

Tests

Here are the results of the tests I took earlier tonight, before co2 had been started for the first time.

GH - 60
KH - 80
PH - 7
NO2 - 0.5
No3 - 20

By my basic knowledge I think all is ideal except No2 which ideally is zero. This was just 4 hours after a 50% water change so wonder if that's why it's showing 0.5. Need to do same test tomorrow and the next day after running co2 routinely from now on.

Any observations on these results from a more experienced person?

David

 

[Byron]

I won't say too much as you seem determined to go high-tech and that is something I have never done so I will leave it for the members with experience.  But I would just mention that this seems a bit extreme just to deal with algae, and I am not convinced you will be successful in this.
 
Algae is natural in any aquatic environment, and it cannot be eradicated, at least not in a healthy system.  But problem algae, meaning algae that suffocates plant leaves, is always due to an imbalance between light and nutrients.  Water flow is not a direct cause.  I have had planted tanks with no filter (obviously, the "dead spots" issue is not an issue either) and thus no water movement at all, and planted tanks with canister filters that send out a fairly strong current.  I see the small black form of brush algae on filter spray bars and tubes where the water is flowing the most rapid (it never spreads further), and I've not had brush algae in the no-flow tanks, so that rather explodes that myth.  CO2 will obviously be involved as it is one nutrient, so this is back to the balance between light and nutrients.  I have dealt with a few outbreaks of brush algae over the years, and always resolved them by lessening the light duration, or reducing liquid fertilizers; in both situations the balance simply had to be re-established.  Cyanobacteria (BGA) is due to high organics in the presence of light; I have had this maybe three times, only in one tank oddly, and with very different fish and plants each time.
 
The water flow has an effect on fish and plants, so one does have to be careful.  I don't know what fish species you have, but a very strong current  does negatively impact many fish and while this is not externally visible, they are wearing down faster simply because they have to expend considerably more energy just to maintain things.  Plants are slower to uptake nutrients in fast water.  So I would be careful here.
 
Byron.

 

[daizeUK]

-Co2

Starting with my first pressurised co2 kit today and building up to 30ppm over the next few days. I have the diffuser in the bottom left rear corner about 7 or 8 inches from the filter intake. I'd say roughly 20% of the bubbles enter the intake. Is this going to be an issue or does it just come out of spraybar?

 
You can position your diffuser right under the intake and try to get as many bubbles through the filter as possible.  It's a recommended practice on many plant forums.  Some people find this causes 'burping' when gas gets trapped in the filter, not me though, my filter never burps.  It's very well behaved
The CO2 bubbles will be held in contact with water for a longer period of time as they travel through the filter pipes thus they will have more time to dissolve which should increase your dissolution rate.
 
I'm also battling BBA and it's a real pain.  I'm squirting it with liquid carbon each day with the filter off and this helps to keep it in check.

 

[David J]

Hi Daize

Good to hear that you have no probs with the bubbles going into your filter. It's been going for 2 days and no problems so far.

I didn't know liquid carbon could be used against it. Might end up giving it a go.

 

[Byron]

Hi Daize

Good to hear that you have no probs with the bubbles going into your filter. It's been going for 2 days and no problems so far.

I didn't know liquid carbon could be used against it. Might end up giving it a go.

I wouldn't recommend using liquid carbon, such as Excel, as this is glutaraldehyde, a highly toxic chemical.  No surprise it sometimes kills brush algae (but not always, as Seachem mention) but it can also kill plants, fish and bacteria if dosed strong enough.  It really is better to resolve the cause rather than band-aiding with chemicals.  The short cut is rarely the best way and the fish need to be considered.

 

[daizeUK]

Oddly, I would usually recommend going with liquid carbon before taking the plunge with a CO2 system.  It does depend on what plants you're growing though as some plants are sensitive to LC and will melt.  Others love and thrive on it.  I also dislike dosing LC in tanks with shrimp as they are a bit more sensitive than fish.