Surface Agitation

[BrianNY]

My 125 gal planted tank is being filtered by an eheim 2217 and a fluval 404. I've the outflows positioned for almost no surface movement. WHat is the best way to deal with the "pond scum" which collects on the surface.

Secondly, I lost a 5 inch brisltenose pleco last night. Since he was the latgest fish in the tank I'm guessing he suffocated due to the O2 being depleted. Any way to confirm this, and if so avoid it in the future?

 

[tkos]

Is this a planted tank? If so then you shouldn't worry about low O2 unless you see the fish gasping for air. Some plecos come starved and just can't make it. From what I understand they have a bacteria in their gut that if not fed will starve and without this bacteria the pleco can't process food. Same thing with ottos.

I guess the pond scum is coming from excess nutrients so see if a more limited feeding will help to reduce the scum. And make sure to clip out dying plant bits (if this is a planted tank).

 

[Enki]

Sad about your pleco. I have a rio powerhead moving water around, it points up at the surface at about a 45 degree angle. This creates a current across the top of the tank and keeps the surface moving all the time.

I drag a clean paper towel (NO additives or perfume!) across the surface as the first thing in my weekly water change/cleaning routine. I found if i do it first, I can get almost all of it. Otherwise, it just gets mixed back into the water as I am fiddling around.

Probably the best solution to scum is a skimmer, but I am not ready for that investment yet.

 

[tkos]

I wouldn't use a skimmer on a freshwater tank, IMO. It will end up stripping too much out of the water, especially for a planted tank. I would stick to the paper towel method or at most use a cup to scoop out the top layer of water prior to a water change.

 

[Guest]

Get a couple black mollies, they supposedly eat the protien scum. For some unknown reason, I had that scum for maybe the first 2-3 months my tank was set up, then it dissapeared. no mollies, no wiping it up, it just went away.

tkos, the skimmer enki was referring to is a surface scum skimmer, designed for fw tanks, not a protien skimmer like they use in sw. Ehiem does make an attachment for this purpose.

 

[tkos]

Okay. Hadn't heard of it. Thanks for the clarification.

 

[BrianNY]

That is good news. It would really be a chore to remove that light everytime I needed to use the paper method.
Thanks
Brian

 

[Enki]

Yeah, I was thinking of the skimmer intake box thingy. I think on my next tank, I'm going to plan ahead for scum and maybe do an overflow box in the back corner for the filter intake.
I only do the paper towel thing during weekly maintenance, so the light and glass tops are off already, but it would be nice to not worry about it at all.

 

[Piscesgirl]

May I ask if you are using C02 or maybe Flourish Excel?

 

[BrianNY]

Well pressurized CO2 was my plan. I have such soft water that I'm going to see how things go without it. But it's a good question about the Flourish Excel. Does anyone have any opinions?

 

[Centurion]

yeah you could put an overflow box in and have the canister draw water from the overflow. it would be very easy to diy one

 

[Piscesgirl]

Well, I have had trouble with my Excel, which is why I asked if you were using that. I also have soft water. I apparently OD'd and killed my CAE by suffocation.

Are you trying to avoid surface movement?

 

[BrianNY]

Yes, I'm trying to limit the surface agitation because here's what I think is occuring:
My water KH is between 1 and 2. Any CO2 in the tank will gas out with a lot of surface agitation causing my PH to rise.

So I think before I start fooling with CO2, I must get the KH up without increasing the PH (which comes out of the tap at 7, and rises to 7.6, 7.7 with 24 hours of aeration). Anyone have any ideas?

 

[Piscesgirl]

That's exactly what happens with my tap water -- but that's because it has C02 in it out of the tap! Doesn't your tank eventually drop back to about 7.0 after the tank is cycled though? That's what usually happens with my cycled tanks unless something is artifically keeping the pH up (like carbonate substances). I tested my water out of my tap (Well water) and it is 28ppm of C02!

I'm assuming your tank is cycled? Or, are you using the plants to cycle the tank? You want some surface agitation.

I'm going to PM you a link to a great article. Lots of info on planted tanks (use only what you need) geared towards the budget-minded hobbyist.

Based on my experience with Excel, I think you are better off trying low dose C02. If you have adequate aeration, it won't hurt, but it might help your plants.

 

[captainGregor]

Could you guys please explain to me at which point one needs to decide on CO2 system. I have plenty of water agitation with airstones and my PH and my plants are growing OK ( i do not have many - see gallery). So, the rhetorical question is - why CO2 and when? Thank you

 

[Piscesgirl]

Well, my understanding is that C02 supplementation is beneficial when you have more than 2 Watts per gallon of light. Some say that you will only get algae if you have more than 2 Watts per gallon of light and do not use C02. I'm still trying to get this clarfied though. I'm going to an aquatic plant club meeting today and if I get a chance, I will ask this question.

 

[BrianNY]

As Pisces girl says Capt. CO2 is in our tap water. The problem is it doesn't stay in solution very long. It gases out and using an airstone or such speeds up the gas out process. Fish of course produce CO2 as they breath, and plants produce O2. So it's a matter of having a well balanced ecosystem in our aquria.

There is a relationship between how much CO2 the water can hold in solution, and KH and PH. The result of adding CO2 to very soft water is a drop in PH which can be deadly to my fish. So if I'm understanding this correctly, I have raise my KH (which will raise my PH), to the point where adding CO2 will lower those levels to an acceptable stable point.

Do I have this right Rex?

 

[Piscesgirl]

Sounds right from what I've read, BrianNY. That should be easily accomplished with a sea shell, as was suggested to me, or buy a bag of a carbonate substrate and put a small spoonful in a small plastic cup in your tank, making it easily adjustable -- put some more, take some out. Easy!

 

[tkos]

Well not all of the CO2 will offgas. The air above the tank and the dissolved gases in the water will reach an equilibrium so the CO2 will escape and then get redissolved. And don't forget that fish give off CO2 as well.

Plants also use some of the hardness in the water and this can lead to pH drops if the hardness is not replenished with sufficient water changes. I just recently found that out with my bigger tank that wasn't getting large enough water changes. My KH is around 1-2 as well. And my brother found out about adding CO2 to softwater the hard way with the loss of his RTBS. So raising that KH is important before adding any CO2.

 

[BrianNY]

Yes, and thanks Tkos. That's why I'm so skeptical of putting my discus in that planted tank. I really need to have everythin under control first.