o2 Oxygenation etc

[Neo]

In a previous post we were discussing o2 saturation in our tanks etc

With my Trigon 190 Zebra Pleco tank which has a fluval u4 with airline to help airate and my eheim external spray bar I was getting results of 6-8mg/l o2

I bought an Eheim 400 air pump which comes with 2x Diffusers as you can see in the attached pic, left it running a good few hours and re tested my o2 and it's the same lol, i thought the extra turbulance would give a higher reading but i was wrong :/ question is do I leave it in as it will probably do more good than harm or take it out, never was much of a bubble bar/wall fan really lol, shall try just a powerhead soon but I have a feeling I wont get above that 6-8mg/l

[apistomaster]

The dissolved O2 saturation point is primarily temperature dependent. At higher elevations water can dissolve less O2 but that matters more if you live above 5000 feet above sea level.
Unless you are testing with a decent quality meter your results are only ball park approximations. I suspect that you are using such a test kit and your actual dissolved O2 levels are remaining quite stable regardless of the combinations you have tried to attain high dissolved O2 levels. H. zebra seem to be very sensitive to many things including dissolved O2. If you haven't seen any signs from the fish that they are in distress I don't think there is anything to be worried about.

[Matt30]

Hi mate if you get a powerhead your going to add more heat so dout it will help,I would adjust your air diffuser so you just have lots of tiny bubbles going to the surface,you will still have surface movement once you have tryed this leave it for a bit then re-test.
And as apistomaster has said your Zebs look fine dont worry about it.

Good luck fella

[apistomaster]

I use a MaxJet 600 power head on one of the two sponge filters I run in all my pleco breeding and grow out tanks. The heat they add is negligible when the fish you keep like to be kept at around 84*F. It means your heaters come on a little less often. Very minimal effect.

The little added heat from a power head is a bigger issue with reef tanks or cold water fish tanks where you want the temps not to exceed 80*F in the case of a reef tanks and may be using many in addition to the main filter pump. Perhaps a power head cold raise the temps in a cold water tank where much cooler temps are desired in cold water tanks.
I use this set up on all my tanks from my 20 Longs to 40 gal breeders.
I mainly keep plecos and wild Discus which all like warm water. I do not want the current from a power head in tanks set up to breed wild Bettas or Killiefish.

[Shane]

The amount of heat added by powerheads can be a deadly issue if the ambient temperature is high, or becomes high seasonally. I spent a lot of time and effort on a high current tank (click My Tanks by my name to see it) and it was a total fail. This was because the ambient temperature was usually in the mid-upper 70s. With three powerheads running, I could not get the tank's temp below 84, which is way too hot for almost all loricariids.

Might be an interesting experiment to record the temp of an unheated 10 gallon tank, add a powerhead, and check the temp again in 24 hours to see how much heat that specific powerhead will add. In my case above, as the tank was a 55 gal, each powerhead was increasing the temp by at least 2 degrees F.

cold water fish tanks where you want the temps not to exceed 80*F

I realize that temperature is a relative thing, but I certainly would not categorize a tank below 80F as "coldwater." I believe that the common definition of a subtropical or coldwater tank is one kept under 68F.


-Shane

[apistomaster]

@Shane,
That sentence which included tanks up to 80*F was poorly written.
80*F is high for a reef tank but deadly for a true cold water tank.

[dw1305]

Hi all,

I would adjust your air diffuser so you just have lots of tiny bubbles going to the surface

If you read the other post on PC <http://www.planetcatfish.com/forum/view ... =5&t=33883> and read the article on aeration at <http://plecoplanet.com/?page_id=829> it explains why you need very small air bubbles with a long residence time in the water column, bubbles are for aquarists not aeration.

The temperature issue from powerheads relates to 2 factors, the wattage of the powerhead (I also use Maxijet/sponge filters, in a very similar manner to Larry), if you think the potential 20W (only some small proportion of which will be dissipated as heat) added by a Maxijet 1200 is too much, you can use a Koralia type pump (although this doesn't add any biological filtration capacity, as you can't fit a sponge too it.)

The other factor is how hard the motor has to work to spin the impeller. If you use coarse PPI10 sponges, and ensure that there are no constrictions in the pipe-work, flow should remain acceptably fast through the powerhead, and little of the power will be converted to heat.

Finally if you have a large enough evaporative surface (e.g. a large volume wet and dry trickle filter) this should provide cooling in almost any conditions.

cheers Darrel

[apistomaster]

I think the MaxiJet 600 only uses 4 watts but it may be 6 watts. Either way, this particular model produces little heat.
It can pump up to 160gph/600lph which is plenty for 20 to 40 gal tanks and as the driver of one of my two sponge filters.
That MaxiJet 1200 would blast the water right out of my small tanks.
I also modified my power head driven sponge filters by cutting 4 X 24 X 1 inch strips; the foam has 20 pores per inch. It provides both mechanical and biological filtration. These permit rapid flow through unless allowed to collect to much dirt. The standard sponge which comes with the filter is fine pore foam intended for use in an air lift mode and which doesn't take long to clog from the strong intake of silt and dirt drawn in by a power head.
They work best after they have collected some dirt. This is true of all non-micron filter media.
This 20 pores per inch foam is easy to clean with a nozzle on a garden hose. The cleaned filter foam retains enough bacteria so as to avoid a significant temporary loss of biological filtration.
I keep it in place with a pair of releasable zip ties which are 16 inches long. The finished sponge filter is close to the same size as the factory configuration but a factory sponge is so fine pored that when used with a power head it is almost impossible to clean.
The only place I could find reusable zip ties was http://www.uline.com, a company which sells all kinds of odds and ends for office and shipping. Everything about the filter is reusable indefinitely except the power heads which sometimes burn out after years of use.
Here is a photo of my modified sponge filters:

[MatsP]

The energy needed to heat 1g of water 1 degree Celsisus is 1calorie, or 4.2J. 1J = 1W * 1s. So 4.2W will heat 1g of water 1degree in one second. Given that 1Wh = 3600J, 1W will heat 1 liter of water 1 degree C in 1 hour and 10 minutes (assuming there is no loss of heat from the tank - in reality there is unless the room temperatre = tank temperature).

It may well be a problem if you put several high power power-heads (and some power-heads are less efficient than others - they do not use ALL the pwer to move water, but losses a lot in heat in the coils used to make the magnetic field to move the water.

But yes, powerheads can increase the temperature of the water. Where I live, in England, it's generally not a problem.

--
Mats