I have a 1/4 acre pond in South/Central Florida. It is in a swampy/wetlands part of the state. We have some walking catfish, tilapia, bluegill, mosquito fish, turtles, snakes and occasionally an otter, haven't seen any gators, but I'm sure there have been some as our neighbors all have. We also have ducks about 12. Bottom soil is sand and muck I believe since the rest of the property is too. The depth is 4-10 feet in dry season (winter/early spring) and 8-14 feet in wet season (summer/fall)
We have planted a lot of trees around the pond and have lotus, pickerel weed, alligator flag and some other aquatic plants, but not sure what if anything is on the bottom. We do not have floating algae or anything like that.
I added colorant and beneficial bacterial and a 24/7 1/4 hp 9000gph floating fountain 3 months ago.
We can see the fish when they come up to feed, except the catfish they're too dark and there in lies my question. I took some water samples and images attached.
The chemistry is: PH 6.4 Ammonia 0 Nitrates 0 Nitrites 0 Phosphates 0.25 ppm
The water sample is slightly green, doesn't look too bad to me, but when looking at the pond it looks dark, blackish, so I can't see too deep. Online research points to tannins, but I would think the sample would be brownish/blackish if that were the case. I know the spring fed ponds here in Florida are crystal clear. I'm not getting millions of gallons of water a day pumped in like they do so I don't expect that, but wondering if I can improve its clarity any more.
Let's see what others have to say about your water color.
Excerpt from Robert Crais' "The Monkey's Raincoat:" "She took another microscopic bite of her sandwich, then pushed it away. Maybe she absorbed nutrients from her surroundings."
You don't need to do it on an expensive tape measure. Just use a thin rope if you have deeper transparency. Maybe put it on a marked piece of 3/4" PVC pipe if it disappears fairly shallow. (Whichever method gives you greater ease of use.)
If you measure your secchi depth at the same time of day, you should be able to easily track the changes in your pond.
Healthy FERTILE ponds usually have your green water this time of year.
Has all of your added colorant disappeared by now? Many of those create dark tints.
Your biggest fertilizer source may actually be the 12 ducks. They are pooping machines! Evicting the ducks would likely give you clearer water - but I suspect you don't want to do that.
Do any oak leaves make it into your pond? That is the most common source of brown/black tinted water due to tannins.
There are actually some species of brown algae. Perhaps they are present with your green algae at certain times of the year?
Congrats on your beautiful pond!
P.S. I suspect at least one of the "models" in your second pond picture greatly enjoys swimming in the pond.
Your water sample looks like a healthy amount of algae to me. That's what I thought, but can only see the fish they're like max 1 foot from surface, with polarized lens too.
There is a simple method of tracking your water clarity using a secchi disk.
Using a Secchi Disk
You don't need to do it on an expensive tape measure. Just use a thin rope if you have deeper transparency. Maybe put it on a marked piece of 3/4" PVC pipe if it disappears fairly shallow. (Whichever method gives you greater ease of use.)
If you measure your secchi depth at the same time of day, you should be able to easily track the changes in your pond.
Awesome thanks, but I guess I don't even know how far down I should be able to see if I do everything right?
Healthy FERTILE ponds usually have your green water this time of year.
Has all of your added colorant disappeared by now? Many of those create dark tints. My guess is yes, since it was dark blue dye and I don't see any of that in the water, plus it's rained enough to double the water volume this summer, so it had to get crazy diluted
Your biggest fertilizer source may actually be the 12 ducks. They are pooping machines! Evicting the ducks would likely give you clearer water - but I suspect you don't want to do that. nah, they make my breakfast, but with the test numbers I saw no nitrates so the plants are likely eating all the good old poo
Do any oak leaves make it into your pond? That is the most common source of brown/black tinted water due to tannins. Definitely, and Pine and about 30 other kinds of trees, but most are evergreen down here so not a ton of leaves, plus what I don't get is if my water sample has no black/brown why does the water look black/brown I figured this ruled out tannins so figured maybe the bottom is that color
There are actually some species of brown algae. Perhaps they are present with your green algae at certain times of the year? maybe, are those the string algae I read about
Congrats on your beautiful pond! thanks I'm blessed, good place for a beer and cigar
P.S. I suspect at least one of the "models" in your second pond picture greatly enjoys swimming in the pond yeah, he loves it, but since I let my wife convince me that he should stay in the house instead of outside at night he doesn't get to go in as much because he has to get washed every time now, old wimpy house dog....
Depending on Algae blooms you can see anywhere from 20” at minimum, up to 40” a few weeks after a bloom has settled. Visually looking at my water I would have never guessed it to be so clear I homemade a Secchi disk
"If you measure your secchi depth at the same time of day, you should be able to easily track the changes in your pond."
"Awesome thanks, but I guess I don't even know how far down I should be able to see if I do everything right?"
There is no "right" answer for pond clarity. The tiny, photosynthesizing algae that make your water green are the base of your entire food chain.
As you diminish the primary producers, then you cannot support as many organisms that are farther up the food chain.
One way to reduce the algae and "clear" the water is to add pond dyes. From reading your post, I assume that the blacker dyes would make your pond LESS attractive to you. There are some dyes that render more of a blue color. That could be more appealing to you AND still reduce some of the sunlight available for algae production.
The other way to reduce algae is to increase the number of rooted aquatic and shoreline plants. Your nitrates might be at zero because it is the algae that are polishing off the last bit of your nutrients? Some more un-invasive shallow water plants or even floating islands might help a bit to make fewer nutrients available for algae growth.
However, your pond might actually be pretty clear right now, but if your bottom is mostly unoxidized muck, then that typically appears black or very dark. Do you have a white painters tarp (or similar material) that you could put on the bottom of a small section? If you can easily observe your fish against a light background, then the pond water itself is not the problem.
If the dark background IS the problem and you want to see your fish more clearly, do you have a nearby source of inexpensive crushed shells or white sand? Maybe you could create a small area with a white bottom? The added calcium carbonate might also help your water quality. If you hand-fed the fish over a white bottom, maybe you could get better observations of your populations? (If you do go that route, make sure you put down ground fabric first. Otherwise your white sand will disappear surprisingly rapidly into the muck.)
I am just throwing out some ideas for you to consider. I am definitely NOT an expert on Florida ponds!
6.4pH is not a healthy algal growing ground. Also, the harder the water the better the algae can survive, but there can be excess nutrients available this time of year, this year seems to be worse than several of the past years. It's been my experience it's always a moving target.
Your water color in the quart jar to me looks like a very strong bloom of phytoplankton. It takes a microscope and an experienced algae person to identify what planktonic algae species are most abundant. Since the water has a green hue I suspect most of the species are the common green algae species and very abundant. Lots of this type of algae are thriving on the nitrates in the water from duck manure to the point of using all the available nitrates thus your chemical test of nitrates = 0. Nitrates grow lush grass and abundant algae. When the nitrate becomes limiting often cyanobacteria begin to bloom. Lots of cyanobacteria species when abundant can also make the water very green. Be watchful of floating green surface film that suggest cyanobacteria that are known to be harmful and problematic.
PS Blue dye as Aquashade when added to water your green will not turn the water a nice blue hue. It takes blue dye with some red in it to make that very green water appear blue.
Last edited by Bill Cody; 09/30/2308:32 PM.
aka Pond Doctor & Dr. Perca Read Pond Boss Magazine - America's Journal of Pond Management
7.0-8.0 depending on the time of day that the reading is taken.
Your biggest headache are the ducks. Things will only get worse over time as long as they are in there. If you can fence off a different area, and have a kiddie pool in there for them where any rainwater or surface water doesn't enter the pond, that is the best thing to do for the pond. A neighbors 1/4 acre pond was kept permanently muddy by 2 ducks. You have 12. If you don't have enough plants in the pond to completely utilize all the nutrients that they are dumping in there, I'd be testing the water for Coliform bacteria and salmonella.
