dinsdag 30 oktober 2012

2012-10-28 09:53 hbos Many divers in water

Weather : overcast/ SSW wind 3 bft / Rain 0.1 mm / 1014.2 hpa
Divers : Mark, Kacper, John, Marcel, Axel
Goal : Video documentation of bottom structure
Max depth : 15.3 mtrs
Duration : 70 minutes
Air temp : 5.7 celsius
Water temp : 13,6 celsius minimum
Fish: > 5 eal embedded in bottom at about 12-14 mtr depth. 1 Zander at about 13 mtrs. Furthermore I've seen no Perch and no Ruffes
Plants : Elodea still stable
Visibility : 7 mtr at 7 meter depth at reel.
Remarks: > 30 divers, No thermocline. We went in the water before the many divers took to the water and we measured visibility. After the many divers submerged. the visibility dropped rapidly. Therefore we canceled the videomaking and just went diving.
There was already much sediment afloat up to a depth of 13 meters. So apparently many divers during the past week have caused this while the wind and natural circulation takes care of the rest.
But that is offcouse logical if the have the choice to dive in Toolenburgplas with a visibility of about 2-3 meters of Hbos with 9-10 mtrs visibility... choice is made very easy.

dinsdag 23 oktober 2012

2012-10-23 20:04 hbos mist is sinking deeper

Weather : overcast/ E wind 2 bft / Rain 0.0 mm / 1023.7 hpa
Divers : Mark, Axel
Goal : Check depth of mistlayer and visibility measurement
Max depth : 18.1 mtrs
Duration : 59 minutes
Air temp : 13.0 celsius
Water temp : 14,0 celsius minimum
Fish: > 3 eals, few perch, and resting Ruffe.
Plants : Elodea is the dominant species but leaves are already getting brownish
Visibility : 10 mtr at 7 meter depth using black/white Secchi shone at with lamp.
Remarks: 2 divers, No thermocline. Very clear water and mist layer is now lowered from 16 to 17 meter depth. Temperature varies from 14.0 to 14,6 so no TC. 
Beautiful clay reefs. Spotted an followed anchor from the NW pontoon and went under the pontoon. The concrete blocks hang at about 12 meters only about 2 meters from the bottom. Lots of old entangled fishinglines on which Christatella Mucedo (mosdiertes) grow at around 9 meters depth. I guess a few caught fish swam over here to deliberately entangle fish lines or people have been fishing from the pontoon. Distance pontoon and shore is about 100 meters. 
The black/white Secchi is the standard for me. Gives perfect and same readings during day with ambient light and in nighttime with a 2200 lumen dive lamp shone from a distance.
In this case 10 meters.

zondag 21 oktober 2012

2012-10-21 10:16 hbos 180 minute dive. airpumps stopped

Weather : overcast/ NE wind 4 bft / Rain 0.0 mm / 1017.0 hpa
Divers : Remko, Iva, Vincent, Thijs, Jan, Axel
Goal : Check SETL plates, visibility and get an overall impression
Max depth : 7.9 mtrs
Duration : 180 minutes
Air temp : 11.0 celsius
Water temp : 14,0 celsius minimum
Fish: > 5 Pike, 2 eals, schools with young perch, 2 eals, 6 jellyfish at about 5-7 meters depth on north and south part of the narrowest part of the lake.
Plants : Elodea is the dominant species, 1 bush of some waterplant.
Visibility : 9,0 mtr at 3 and 10 mtr at 6 meter depth using Sechhi.
Baseline meter gave 6,5 meters where the divers could clearly be seen.
Remarks: > 10 divers, No thermocline. Very clear water. 

SETL H135 (white tiewrap) : stable. Only algea grows on side and on top of the plate.
SETL H136 (black tiewrap) : Totally clean probably due to diver bubbles.
In SW corner the visibility was reduced probably due to NE wind. Only the NE side has more fish.
passed 3 fishing lines with 1 dead herring as bate.  The lake is getting clearer now that the airpumps have stopped.


zaterdag 13 oktober 2012

2012-10-11 20:04 hbos eals and Carp. Last watersamples

Weather : lightclouds / OSO wind 3 bft / Rain 0.1 mm / 1009.2 hpa
Divers : Remko,Ben, Axel
Goal : Check SETL plates, watersamples , visibility, in search of Thermocline
Max depth : 18,4 mtrs
Duration : 87 minutes
Air temp : 9,5 celsius
Water temp : 15,6 celsius minimum
Fish: > 3 young Pike, 4 eal, school with common roach about 10 cm feeding on the explosion of shrimp. 1 Carp, 1 giant copepod.
Plants : Elodea is growing upto 7 meters with white roots. Very few algea dots only on north side
Visibility : 5,0 mtr at 5,5 and 6 meter depth.  (baseline meter because of bad light conditions)Remarks: 3 divers, No thermocline. a little milky. Down to 18 meters the temperature is constant. Mist layer starting at 17 meters.

CO2 is still pretty high and PH is fairly low probably due to much rainfall lately.
SETL H135: Few dots of brown coloured growth is starting. Few threads of tube algea attached to it
SETL H136: Just a brownish glow at the outer corners of the plate few threads of tubealgea landed on it and a few waterfleas have gathered underneath it.

woensdag 3 oktober 2012

2012-10-02 19:55 hbos SETL H135 growth after 5 days!!

Weather : sheep clouds / SSW wind 4 bft / Rain 0.05 mm / 1011.9 hpa
Divers : John, Thijs, Axel
Goal : Check SETL plates, watersamples , visibility
Max depth : 10,4 mtrs
Duration : 54 minutes
Air temp : 12.7 celsius
Water temp : 16.8 celsius minimum
Fish: > 1 young Pike, 1 eal, > 5 bigger perch active, larger snails, active shrimp in and near clayblocks.
Plants : Green algea diminishing. rest of plants is stable. Elodea not growing deeper than 7-8 meter. Pile at 3 meter suddenly showing more tube algea.
Visibility : 5,5 mtr at 3 and 6 meter depth.  (baseline meter because of bad light conditions.
Remarks: 3 divers, No thermocline.many free floating algea.

SETL H135: Few dots of brown coloured growth is starting. Few threads of tube algea landed on it
SETL H136: Just a brownish glow at the outer corners of the plate few threads of tubealgea landed on it.