Pond Boss Forums AERATION Systems questions New aeration system installed!

Just to share, I saved up and had a new aeration system installed a few days ago. I went with a AquaMaster rotary vane pump, remote manifold for 4 bottom diffusers. I have a 2.5 acre pond, ave depth ~9 feet. Not sure if it's okay to post the name of the business I used to do the job, but if the mod's say okay I will, or you could PM me if you wanted to know. I live in Iowa, and so chose a local business.
The air is an important 'step one' in our long term management plan for this pond. Being nearly 40 years old, with lots of mature oak trees around it, it was becoming heavily eutrified. I am hoping to begin reversing this process, and after going through "Pond Boss Forum school", felt bottom aeration was a key step. I'm adding a couple pictures.
all the best to the PB crew,

Luke

Dr. Luke, thank for the update and I'm very eager to hear your success!

I'm not sure what aeration does to the bottom when the depth is 9'. I know you should have less problems with water temp stratification if your depth stays at or less than 9'. I know my pond is about 9' now, was more like 6' last summer before I sealed the leak in the bottom. Still over even a 6' depth differential there is a warm surface and cool bottom. Even with my aerator running I couldn't 'mix' the water enough to get rid of that temperature differential. I run it 12 hours every night when the weather warms to try to keep the pond from getting to hot in the summer.

I know your goal was like mine, to avoid muck buildup and help circulate water via the tiny bubbles. I had hoped it would prevent muck build up, but in my very tiny pond, the oak leaves overwhelm the pond. I'm curious what you do with the leaves that fall in? Do you try to rake them out?

My shore line leaves on the shores that have mature oak and maple trees tend to just sit there and not breakdown. I know they are good hiding spots for minnows, scuds, ghost shrimp and crays. I'm afraid if I go rake them out that I'll take out some desirables too. However when I was dredging around with a long handled rake in the middle of the pond last year trying to snag my aerator, I turned up lots of very nasty blackened clumps of leaves. Apparently there is a layer of black decaying leaves right at the bottom in the middle where aeration is the best too. So, not sure what i can expect.

I'm tempted because my pond is small to use mechanical agitation (dragging something on the bottom, rent a trash pump and use a weighted section of hose to blast water all over the bottom, or use an outboard motor directed down at an angle) to stir up the pond. I know the leaves will probably just settle back down again but at least they will get mixed and aerated in the process?

If bottom diffusion aeration is not destratifying the pond to me that means one of three things:

1) The system is undersized for the pond or the diffusers are not placed properly in the pond.

2) The diffusers are getting clogged up and don't lift the same GPM of water to the surface as they did when first installed.

3) The system isn't run for enough hours of the day.

For instance, if an aeration system is designed for a pond and it will turn over the pond volume once per day, then running it for only 12 hr per day will only move 1/2 the pond volume. Aeration systems are typically designed to run 24/7 unless other specs are desired.

CanyonCreek-
We have so many mature Oaks around the pond (a dense 7 acres along one side, plus well spaced mature trees on the other sides) that raking out would be impractical. We DO mow up and vacuum up the leaves during the fall drop. We purchased a leaf vac from DR Power, and pull it behind the mower. We are able to collect and reduce mountains of leaves this way. And since they've been through both the mower and the leaf vac (which pulverized them some more) they come out crushed to bits; this helps them break down much faster. We had a pile from last fall that would have filled two semi trailers easily, but is 2/3 flattened this spring.

We do have modest hopes for improved water quality from the aeration, but I've read enough posts from Bill Cody and others that I do not expect miracles by any means. But if the resident bacteria are able to kick it into high gear with the newly oxygenated bottom, we are hoping they have some success. We have researched adding biologics, and may try this next year with the 'pond budget'.

esshup, can you define destratification for Dr. Luke and I who have 9' depth? Do you mean that surface temp will equal temp when sampled at the bottom at 9'? That seems impossible so not sure what goal we can expect.

Last summer when I put a hollow handle landscape rake rapidly to the bottom you could feel that cold water from depth rising up the open handle and I could feel the clear temp differential at the top where the cold water was pouring out. I can't begin to guess what the temp difference was but probably it was like 78 at the top and 62-65 at bottom as a very rough guess?

Sue calculated my pond size, gallons of water and sized my system accordingly. I will say my pond stays 'fuller' post-Soilfloc than it ever did so I may want to go from a single station with 2 vertex diffusers to two stations and 4 diffusers to cover my new larger volume of water. But before doing that I'd like to know what temperature difference we should be shooting for.

Also, will aeration ever get one to the goal where that decaying layer of oak leaves on the bottom will not be nasty/black/stinking? I would like to see what Dr. Luke reports on the condition of his oak leaves both at the shallow depths and at the deeper waters.

esshup-
We plan to run our air 24/7 until freeze up, and then only the shallow water diffuser. I chose to hire a professional exactly for concerns about correct system design and diffuser placement. We also chose diffusers that are so called 'self cleaning'. I may pull one up after the summer season is over, just to see how clean they are staying, and again in a year. My installer stated he'd pulled these same diffusers after 4 years with them looking clean as day 1.

You will/might see a few degrees difference, but not a drastic change from top to bottom. Definitely not a thermocline temp difference.

Esshup, along those lines, how do other pond owners measure temps? Simple (water tight) mercury thermometer, stuck down in the water? And on the bottom? Did I read somewhere about putting the thermometer in an old plastic pop bottle, and lowering to the bottom?
Just curious. It's always nice to work with hard data on such things.

Many different ways, depending on the pond owner.

Everything from a YSI Optical O2 meter w/temp probe to a swimming pool thermometer on a string dropped to the bottom and pulled up fast. There's a recent thread about thermometers for ponds.

You can also buy digital aquarium thermometers that have a probe on a lead about 6-10 feet long.

DrLuke, I hate to say it, but "self Cleaning" diffusers only keep the holes fairly clean when properly "flexed". It is the crap that grows over the holes that makes the bubbles coagulate into larger bubbles.

Rainman, remind me how a guy can 'flex' his diffusers? I'm sure I read about it on here somewhere, but can't recall exactly how. Shutting down the manifolds until only one diffuser is getting air flow?

off/on cycles.

BUT, the only way to get them clean is turn system off, pull up and manually clean. That's why I like to either install a line with a float to the diffuser assembly or use a grappling hook on a rope.

I prefer the rope/float method for most types of diffuser assemblies.

For multiple diffuser pods, turn off the compressor, close all but one valve to isolate air flow to a single diffuser or array, turn on your compressor and watch your pressure gauge to ensure it does not exceed 15 psi or you may blow the diffuser membrane out of it's retainer ring. Cycle each diffuser/array 5-10 times individually by turning the compressor on and off with about a 30 second pressurization, switch pump off... after pressure falls back to zero psi turn pump back on for each cycle.