Re: Regarding your DO Saturation testing in bass boat livewells full of fish - Rivermont Jeff
Thanks Jeff-
Night tournament – calculated DO saturations estimating your barometric pressure @ 300 ft above sea level, 0.0 salinity. DO Saturation calculator
http://water.usgs.gov/software/DOTABLES/
79/7.4 DO Sat 90%
76/7.7 ---------- 82%
67/3.6 ---------- 38% *** Non Functional Livewell
75/6.4 ---------- 74%
73/6.1 ---------- 69%
72/6.2 ---------- 69%
84/3.4 ---------- 43% *** Non Functional Livewell
78/6.9 ---------- 83%
Release tank
74/6.1 DO Sat 70% no fish or O2 in live well
74/ 8.4 DO Sat 97% fish and O2 injected *** Excellent DO for stocking density
Next time you test, please note your DO Saturation along with DO Concentration and water temperature please. Your barometric pressure should auto-adjust with your meter. I took a guess at your elevation above sea level and salinity.
I see only 2 non-functional livewells with deadly DO water quality. These 2 may have had a heavy stocking density that exceeded the aerator’s capabilities to safely oxygenate the livewell water, fish slowly suffocated in these 2 livewells. The other livewells probably had a lighter bio-load (less weight of the total catch) and were certainly not overstocked and had tolerable DO’s.
Night tournaments historically have higher mortality than day tournaments because photosynthesis stops at night and the DO falls. Mother Nature at work, aquatic plants use O2 at night, they don’t make it.
“The release tank is a 100 gallon tank the holds fish for a few minutes after they have been weighed just to give them a good dose of O2 before being released.” A few minutes of supplemental oxygen at the last moment may only palliative, but it’s be better than no oxygen for the last high stress boat ride of the night. That’s sort of like giving a cardiac patient a few minutes O2 in ER and discharging him.
Looking forward to reviewing you next DO testing with H2O2 additives.
You’re doing a great job as are most of the anglers wells that you tested, ya'll keep up your great work and research. No doubt your are opening many eyes to new unseen facts about livewell water quality.
“Keep in mind any level below 5.0 fish begin to stress”…
This 5 PPM DO concentration value your speak about is for fish living undisturbed in the steady state environment – highly stressed captured wild fish being transported in a confined livewell space is a very different matter, much more dissolved oxygen is necessary for high stress, high density transport conditions in the summer. Contact and ask any fish hatchery manager in any state or any bait dealer that sells live shiners about this, they know about this too. Unlike a fellow in a fishing tournament, if their fish die in transport, they are probably going to lose their job.
Check this out:
Oxygen – How much oxygen do Live bait and Tournament Game Fish need in summer livewells and bait tanks for all day transports?
The Environmental Protection Agency (EPA) stated many years ago in the last century that 5 PPM (parts per million) dissolved oxygen concentration is safe for fish living undisturbed in natural environmental waters.
The EPA says 5 PPM DO is an acceptable and satisfactory dissolved oxygen water quality parameter for wild fish living in the steady state environments in lakes, reservoirs, rivers, ponds, etc. provided the fish are not under constant, severe, extreme stress or in hostile overcrowded conditions commonly found in fishermen’s livewells and bait tanks every summer .
Fish hatcheries and fishery biologist say 100% dissolved oxygen saturation in necessary when transporting live mature and juvenile bait fish and mature tournament caught game fish is a very different matter when it comes to how much dissolved oxygen is required and necessary to have a safe live haul tank “livewell/bait tank” DO environment.
100% DO SATURATION OR GREATER (DO SUPERSATURATION) is required and considered minimal safe oxygenation by all fish hatcheries for all live fish transports… even for transporting only 1 fish (TP&WD “Share a Lunker”- Bass Conservation Program in Athens, TX).
DISSOLVED OXYGEN
What’s DO Concentration and DO Saturation all about?
DO Concentration is measured in parts per million (PPM DO or ml/L DO)
DO Saturation is measured in volume % Saturation (% DO Sat)
Unfortunately there is not simply one DO concentration water quality standard used to define minimal healthy dissolved oxygen environments for wild and cultured fish being transported and living normally in natural wild environments. That is because transport environments, stocking densities and water quality conditions vary and are not “steady state.” The DO requirements are different.
Live fish and live bait being transported must have more oxygen than normally found in the steady state environment. Fish are exposed to many environments in the wild and diverse, stressful captive environments. There are many water quality standards and requirements, specifically safe dissolved oxygen (DO) requirements that apply to different aquatic environments and specific live fish transport conditions. Oxygen deprivation kills in seconds and minutes in live transport tanks, boat livewells and bait tanks.
We’ve all heard of and are familiar with 5 PPM DO. This is the EPA DO Concentration Standard for lakes, rivers, ponds, etc. that applies to normal “steady state environments.”
Fishermen transporting captured live wild bait fish and mature tournament caught game fish, then transported all day, 6-8 hours, in small overcrowded aerated boat livewells in harsh summer tournament conditions is as far from the EPA “steady state environment” and controlled fish hatchery environment as we are from the moon. The difference is vast.
EPA Environmental Water and Waste Water – Professional
• Dissolved oxygen EPA Standards for Environmental Water – 5 PPM DO concentration
• Sewage waste water discharge – 5 PPM DO concentration
Home Aquarium -Tropical Fish – Non-Professional
• Aquarium water at home – 3-5 PPM DO concentration
Fish Culture – Professional
• Hatchery – pond water – 5 PPM DO concentration
• Hatchery – intensive live haul transport water – 100% DO Saturation
• Hatchery – intensive fish culture water – 100% DO Saturation
• Hatchery – intensive closed culture recirculating system water – 100% DO Saturation
Sport Fishermen – Boat livewell, Bait Tanks, tournament release Boat Tanks and Holding Tanks – Non-Professional
• Livewell water in sport fishing boat livewells (small water volume to high stocking density) – 100% DO Saturation
• Fishing tournament live release boat tanks – 100% DO Saturation
• Fishing tournament holding tanks – 100% DO Saturation
All State, Federal and private fish hatchery dissolved oxygen standards for live fish transport is 100% DO Saturation or DO Supersaturation >100% DO Saturation whether transporting one live fish or one thousand pounds of live fish. Contrary to some beliefs, you cannot harm, kill or poison live fish during 6-8 hour transport with “too much pure oxygen.”
Reversing that cellular oxygen debt as quickly as possible, seconds after landing the fish or netting the bait is vitally important for fish health if reducing acute and delayed tournament mortality is a goal.
You will need additional supplemental oxygen for this, can’t reverse sever cellular hypoxia with air (aeration) in the summer, this hypoxic insult is too severe and ongoing lasting for 7-8 hour bass boat ride all day. This chronic cellular suffocation takes a serious toll often resulting in tournament fish kills and post tournament disease in the summer. Hours of hypoxic stresses weakens the fish’s immune system predisposing it to disease - if it survives the initial hypoxic insult on tournament day. There is simply nothing positive about hypoxic stress and should be avoided at all cost.