FAQs

Preparation and Use: PolySeed®

Product Information
1. What is PolySeed's shelf life?
2. What material is the PolySeed capsule made of?
3. How should PolySeed be stored?
4. How many individual tests can one capsule of PolySeed perform?
5. Are there any nitrifying organisms in PolySeed?

PolySeed Preparation and Use
6. How do I rehydrate PolySeed?
7. What do I add the contents of the PolySeed capsule to?
8. Can I use deionized water to prepare my PolySeed solution?
9. When preparing the PolySeed solution, can I just drop the capsule in the dilution water?
10. Should I start my test over if a piece of PolySeed capsule falls into the dilution water?
11. If bran is introduced into the BOD bottle will it adversely affect the 5-day dissolved oxygen uptake rate?
12. How long is the prepared PolySeed solution good for?
13. What dilutions should I use when performing the test?
14. What type of BOD bottles should I use?

Test Results: Getting the Results You Want
15. What should the DO depletion be for the largest volume of PolySeed solution (25 mls)?
16. Is the 5-day Dissolved Oxygen Uptake associated with the microbes or the bran?
17. What should I do if I get High SCF and High GGA results?
18. What should I do if I get High SCF and low GGA results?
19. What should I do if I get low SCF and High GGA results?
20. What should I do if I get low SCF and low GGA results?
21. What should I do if my SCF results fall within the correct range but my GGA results are too high?
22. What should I do if my SCF results fall within the correct range but my GGA results are too low?
23. What should I do if my GGA results fall within the correct range but my SCF results are too high?
24. What should I do if my GGA results fall within the correct range but my SCF results are too low?

1. What is the shelf life for PolySeed?

PolySeed has a shelf life of 2 years. If your PolySeed is close to or has passed the expiration date, you should order a new bottle.

2. What material is my PolySeed capsule made of?

The PolySeed capsule is made of food grade gelatin.

3. Under what conditions should PolySeed be stored?

  1. Temperature range: PolySeed should be stored between 65-80°F (18-25°C). If PolySeed has been stored outside of this range, microbial activity may be diminished.
  2. Humidity: PolySeed should be stored in a dry area. If PolySeed is stored near a moisture source, microbial activity may be diminished. If the product inside the PolySeed capsule is difficult to pour into the dilution water, your PolySeed may have absorbed moisture in storage.
  3. Location: PolySeed should be stored away from any source of heat and light. This includes ovens, autoclaves, furnaces and direct sunlight.

NOTE: When storing PolySeed, make sure the bottle is closed tightly. If the bottle has not been kept closed, environmental conditions may adversely affect microbial activity.

4. How many individual tests can one capsule of PolySeed perform?

One capsule of PolySeed per 500mls of dilution water can be used for 100-125 tests depending on the amount of seed used per test.

5. Are there any nitrifying organisms in PolySeed?

No, PolySeed is made from pure sporulated cultures containing no nitrifying organisms. To survive, nitrifiers must have moisture. The bran that acts as a carrier for the microbes in PolySeed is not conducive to nitrifiers growth.

6. How do I rehydrate PolySeed?

  • Open the PolySeed capsule and pour the contents into 500mls of dilution water. (We recommend 500 mls however, this amount may be adjusted to achieve a SCF between 0.6-1.0mg/L)
  • Aerate the PolySeed solution for 1 hour using an aquarium pump and diffusers (the vortex method is not recommended) while mixing on a magnetic stirrer.
  • After aerating and stirring for 1 hour let the PolySeed solution settle for 15 minutes (in the beaker or in a separatory funnel)
  • Decant the PolySeed solution to eliminate the bran. You can slowly pour your solution into a clean beaker or you can use a separatory funnel.
  • Place the PolySeed back on the magnetic stirrer and gently stir throughout the remainder of the test. This will keep the solution from stratifying.

7. What type of water should I add the contents of the PolySeed capsule to?

The PolySeed capsule must be added to BOD/nutrient water only. The BOD/nutrient water is used for ionic balance. The chemical balance inside each microbial cell in the PolySeed must be equal to the chemical balance in the water surrounding the cell. If the microbes in PolySeed were rehydrated in plain deionized water, the differential pressure between the water phase outside and inside the cells will cause the cells to lyse (explode/tear) within a few minutes.

8. Can I use deioned water to prepare my PolySeed solution?

No. The PolySeed solution must be prepared with BOD/nutrient water only. The BOD/nutrient water is used for ionic balance. The chemical balance inside each microbial cell in the PolySeed must be equal to the chemical balance in the water surrounding the cell. If the microbes in PolySeed were rehydrated in deionized water, the differential pressure between the water phase outside and inside the cells will cause the cells to lyse (explode/tear) within a few minutes.

9. When preparing the PolySeed solution, can I just drop my capsule into the dilution water?

No, the PolySeed capsules are not readily soluble. To use PolySeed, you must open the capsule and pour the contents into the dilution water. For optimum activity, ensure that all of the capsule contents are added to the dilution water.

10. Should I start my test over if a piece of the PolySeed capsule falls into the diution water?

Yes. Although the capsule is made of food grade gelatin, we recommend you start over. The BOD test has many variables and you don't want to take any chances.

11. If bran is introduced into the BOD bottle will it adversely affect the 5-day dissolved oxygen uptake rate?

Yes. The bran is simply a carrier for the microbes. Once the PolySeed is hydrated, the microbes soak off the bran. The bran is not a primary food source. Bran should not be present in your test; therefore it is very important not to draw any bran into your pipette. This is why we highly recommend you decant your PolySeed solution after the solution has been hydrated.

12. How long is the prepared PolySeed solution good for?

The PolySeed solution will remain active for up to 6 hours. If you test runs over 6 hours, it is necessary to prepare fresh solution.

13. What dilutions should I use when performing the test?

Dilutions Summary

  • Use 2 dilution water blanks
  • Use 3 Seeded controls - preferably, 15, 20, 25 ml PolySeed solution & fill to 300 ml with dilution water. However you can adjust these dilutions based upon your experience. For instance, we use 20, 24, 28 ml of PolySeed for our seeded controls.
  • Use 2 Glucose/Glutamic acid controls - 6.0 ml GGA solution, 4 ml PolySeed solution & fill to 300 ml with dilution water.
  • Add 4 ml PolySeed solution to each sample bottle.

Note: We monitor PolySeed at these dilutions, as they are the ones used most commonly in labs all over the world in order to meet Standard Methods criteria. The calculations from these controls can help us determine conditions in your lab to help you meet criteria.

14. What type of BOD bottles should I use?

To ensure a water tight seal, InterLab Supply recommends using Wheaton’s 300-mL BOD bottles.  Wheaton’s BOD bottles have a flared mouth and use tapered ground-glass stoppers which are the bottle features recommended in The Standard Methods for Examination of Water and Wastewater.

15. What should the DO depletion be for the largest volume of PolySeed solution (25 mls)?

It is important that the largest volume of PolySeed solution deplete the DO by at least 50%. This indicates good microbial activity in your PolySeed solution.

16. Is the 5-day Dissolved Oxygen Uptake associated with the microbes or the bran?

The dissolved oxygen uptake rate (DOUR) is associated with the microbes in PolySeed. The bran is simply a carrier for the microbes and not a food source, although it can be with time (normally over 6 hours). Once PolySeed is hydrated, the microbes soak off of the bran. No bran should be used in your test so it is very important to not draw any bran into the pipette.

17. What should I do if I get High SCF and High GGA results?

Is the GGA fresh and of high quality? Always insure that the GGA solution has not expired and has not been contaminated. Remember, exposure to air can biologically contaminate the GGA solution.

Has your labware been properly cleaned? Always properly clean and store your bottles, pipettes, tubing, air stones, etc. Sterilization of air stones and tubing is not recommended.

Has your technique changed? Make sure that your technique is proper and consistent, paying special attention to your pipetting technique.

Have you checked the water quality? The DI/Distilled water pH should be between 6.5 and 7.5 with a conductivity of less than 1.0 micromhos. The BOD water pH should be 7.2+-0.2 with a conductivity of 125 - 160 micromhos.

Finally, have you reviewed and are properly following the current PolySeed application procedures? A copy of these procedures is provided with each bottle of capsules or liquid and should be reviewed regularly for changes. These procedures can also be downloaded from our website.

Next, after the above has been addressed and problems still exist, do the following:

Increase PolySeed rehydration dilution water by 50-250 mls. This process is approximately linear so if you need to reduce the SCF 20% you should increase the dilution water by 20%.

After this adjustment and your SCF falls into range but you are still having problems with high GGA, decrease the amount of seed in your GGA's and/or samples by 1-2 mls which will lower the GGA.

18. What should I do if I get High SCF and low GGA results?

• Is the GGA fresh and of high quality? Always insure that the GGA solution has not expired and has not been contaminated. Remember, exposure to air can biologically contaminate the GGA solution.

Has your labware been properly cleaned? Always properly clean and store your bottles, pipettes, tubing, air stones, etc. Sterilization of air stones and tubing is not recommended.

Has your technique changed? Make sure that your technique is proper and consistent, paying special attention to your pipetting technique.

Have you checked the water quality? The DI/Distilled water pH should be between 6.5 and 7.5 with a conductivity of less than 1.0 micromhos. The BOD water pH should be 7.2+-0.2 with a conductivity of 125 - 160 micromhos.

Finally, have you reviewed and are properly following the current PolySeed application procedures? A copy of these procedures is provided with each bottle of capsules or liquid and should be reviewed regularly for changes. These procedures can also be downloaded from our website.

Next, after the above has been addressed and problems still exist, do the following:

Increase PolySeed rehydration dilution water by 50-250 mls. This process is approximately linear so if you need to reduce the SCF 20% you should increase the dilution water by 20%.

After this adjustment and your SCF falls into range but you are still having problems with low GGA, increase the amount of seed in your GGA's and/or samples by 1-2 mls which will increase the GGA.

19. What should I do if I get low SCF and High GGA results?

• Is the GGA fresh and of high quality? Always insure that the GGA solution has not expired and has not been contaminated. Remember, exposure to air can biologically contaminate the GGA solution.

Has your labware been properly cleaned? Always properly clean and store your bottles, pipettes, tubing, air stones, etc. Sterilization of air stones and tubing is not recommended.

Has your technique changed? Make sure that your technique is proper and consistent, paying special attention to your pipetting technique.

Have you checked the water quality? The DI/Distilled water pH should be between 6.5 and 7.5 with a conductivity of less than 1.0 micromhos. The BOD water pH should be 7.2+-0.2 with a conductivity of 125 - 160 micromhos.

Finally, have you reviewed and are properly following the current PolySeed application procedures? A copy of these procedures is provided with each bottle of capsules or liquid and should be reviewed regularly for changes. These procedures can also be downloaded from our website.

Next, after the above has been addressed and problems still exist, do the following:

Decrease PolySeed rehydration dilution water by 50-250 mls. This process is approximately linear so if you need to increase the SCF 20% you should decrease the dilution water by 20%.

After this adjustment and your SCF falls into range but you are still having problems with high GGA, decrease the amount of seed in your GGA's and/or samples by 1-2 mls which will lower the GGA.

 

20. What should I do if I get low SCF and low GGA results?

• Is the GGA fresh and of high quality? Always insure that the GGA solution has not expired and has not been contaminated. Remember, exposure to air can biologically contaminate the GGA solution.

Has your labware been properly cleaned? Always properly clean and store your bottles, pipettes, tubing, air stones, etc. Sterilization of air stones and tubing is not recommended.

Has your technique changed? Make sure that your technique is proper and consistent, paying special attention to your pipetting technique.

Have you checked the water quality? The DI/Distilled water pH should be between 6.5 and 7.5 with a conductivity of less than 1.0 micromhos. The BOD water pH should be 7.2+-0.2 with a conductivity of 125 - 160 micromhos.

Finally, have you reviewed and are properly following the current PolySeed application procedures? A copy of these procedures is provided with each bottle of capsules or liquid and should be reviewed regularly for changes. These procedures can also be downloaded from our website.

Next, after the above has been addressed and problems still exist, do the following:

Decrease PolySeed rehydration dilution water by 50-250 mls. This process is approximately linear so if you need to increase the SCF 20% you should decrease the dilution water by 20%.

After this adjustment and your SCF falls into range but you are still having problems with low GGA, increase the amount of seed in your GGA's and/or samples by 1-2 mls which will increase the GGA.

21. What should I do if my SCF results fall within the correct range but my GGA results are too high?

• Is the GGA fresh and of high quality? Always insure that the GGA solution has not expired and has not been contaminated. Remember, exposure to air can biologically contaminate the GGA solution.

Has your labware been properly cleaned? Always properly clean and store your bottles, pipettes, tubing, air stones, etc. Sterilization of air stones and tubing is not recommended.

Has your technique changed? Make sure that your technique is proper and consistent, paying special attention to your pipetting technique.

Have you checked the water quality? The DI/Distilled water pH should be between 6.5 and 7.5 with a conductivity of less than 1.0 micromhos. The BOD water pH should be 7.2+-0.2 with a conductivity of 125 - 160 micromhos.

Finally, have you reviewed and are properly following the current PolySeed application procedures? A copy of these procedures is provided with each bottle of capsules or liquid and should be reviewed regularly for changes. These procedures can also be downloaded from our website.

Next, after the above has been addressed and problems still exist, do the following:

If your SCF falls into range but you are having problems with high GGA, decrease the amount of seed in your GGA's and/or samples by 1-2mls which will lower the GGA.

22. What should I do if my SCF results fall within the correct range but my GGA results are too low?

• Is the GGA fresh and of high quality? Always insure that the GGA solution has not expired and has not been contaminated. Remember, exposure to air can biologically contaminate the GGA solution.

Has your labware been properly cleaned? Always properly clean and store your bottles, pipettes, tubing, air stones, etc. Sterilization of air stones and tubing is not recommended.

Has your technique changed? Make sure that your technique is proper and consistent, paying special attention to your pipetting technique.

Have you checked the water quality? The DI/Distilled water pH should be between 6.5 and 7.5 with a conductivity of less than 1.0 micromhos. The BOD water pH should be 7.2+-0.2 with a conductivity of 125 - 160 micromhos.

Finally, have you reviewed and are properly following the current PolySeed application procedures? A copy of these procedures is provided with each bottle of capsules or liquid and should be reviewed regularly for changes. These procedures can also be downloaded from our website.

Next, after the above has been addressed and problems still exist, do the following:

If your SCF falls into range but you are having problems with low GGA, increase the amount of seed in your GGA's and/or samples by 1-2mls which will increase the GGA.

23. What should I do if my GGA results fall within the correct range but my SCF results are too high?

• Is the GGA fresh and of high quality? Always insure that the GGA solution has not expired and has not been contaminated. Remember, exposure to air can biologically contaminate the GGA solution.

Has your labware been properly cleaned? Always properly clean and store your bottles, pipettes, tubing, air stones, etc. Sterilization of air stones and tubing is not recommended.

Has your technique changed? Make sure that your technique is proper and consistent, paying special attention to your pipetting technique.

Have you checked the water quality? The DI/Distilled water pH should be between 6.5 and 7.5 with a conductivity of less than 1.0 micromhos. The BOD water pH should be 7.2+-0.2 with a conductivity of 125 - 160 micromhos.

Finally, have you reviewed and are properly following the current PolySeed application procedures? A copy of these procedures is provided with each bottle of capsules or liquid and should be reviewed regularly for changes. These procedures can also be downloaded from our website.

Next, after the above has been addressed and problems still exist, do the following:

If your GGA falls into range but you are having problems with high SCF, increase the PolySeed rehydration dilution water by 50-250 mls. This process is approximately linear so if you need to decrease the SCF by 20% you should increase the dilution water by 20%.

24. What should I do if my GGA results fall within the correct range but my SCF results are too low?

• Is the GGA fresh and of high quality? Always insure that the GGA solution has not expired and has not been contaminated. Remember, exposure to air can biologically contaminate the GGA solution.

Has your labware been properly cleaned? Always properly clean and store your bottles, pipettes, tubing, air stones, etc. Sterilization of air stones and tubing is not recommended.

Has your technique changed? Make sure that your technique is proper and consistent, paying special attention to your pipetting technique.

Have you checked the water quality? The DI/Distilled water pH should be between 6.5 and 7.5 with a conductivity of less than 1.0 micromhos. The BOD water pH should be 7.2+-0.2 with a conductivity of 125 - 160 micromhos.

Finally, have you reviewed and are properly following the current PolySeed application procedures? A copy of these procedures is provided with each bottle of capsules or liquid and should be reviewed regularly for changes. These procedures can also be downloaded from our website.

Next, after the above has been addressed and problems still exist, do the following:

If your GGA falls into range but you are having problems with low SCF, decrease the PolySeed rehydration dilution water by 50-250 mls. This process is approximately linear so if you need to increase the SCF by 20% you should decrease the dilution water by 20%.

 

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