Nitrate reactor redox problem/rotten eggs smell

Answer:

Paul
I have this reactor and this week I realised that the water was not going round the reactor even though the pump was running.I was getting the rotten egg smell too but do not use a redox probe as it is not necessary other than to see what is going on.

I took the lid off and found that the central pipe was completely filled up with a thick bacterial jelly. I took a salt bucket and emptied the contents into it then scraped off as much junk as I could before reassembling.
Next I filtered the water back into the unit and topped it back up.

For the next 12 hours I left it with no additional water flow and the reactor is now running again on normal flow.

What flow rate are you passing through and how much alcohol are you using?
Is this vodka and if so how strong are you using it?

Regards
Stuart

Response

hi stuart

 thanks for the reply,i am dosing 3 parts ro 1 part vodka,i am only  dosing 8 ml a day because of the bad egg smell,but the redox reading has still not come down,the flow through the reactor can be quite quick if needs be.i think i will do what you have done and then see what happens,also it might bring the redox back to -170 if i do that.any more help or advice would be grateful.

 thanks paul

D-D Response

What is the actual flow rate at the moment?

Response

hi stuart

 i have got the nitrate filter running of a tee of my skimmer,the flow coming out of the filtert is a fast drip rate ,if this is what you mean.

thanks paul

D-D Response

You need to measure the flow with a measuring jug and a stop watch

 What size is the tank too?

Response

How long on the stopwatch,and the tank is 9ft-3ft-30 +inches.

 Thanks paul

D-D Response

Paul
 It does not matter how long as long as you can measure the amount of water.
 You could collect for 1 minute and then use a test kit syringe to draw out the water and measure how much has been collected in 1 minute

 Stuart

Response

Hi stuart,

 Thanks for the reply,how much water am i ment to collect in 1min.

 Thanks paul

D-D Response

Paul

Just check it and let me know what you get so that I can do a few
calculation for you.

 Stuart

Response

hi stuart,it is roughly between 60-70ml per min.i have worked out as it should be between 65 and 70 ml per min as instructed on the website instructions,for the entire tank to go through in 21 days.

thanks paul

D-D Response

Paul
I would up the flow to about 85 mls per minute which will give you a turnover of 14 days and should bring down the redox.
Try this for a few days and see how it affects the redox.

If this does not bring it down then slowly cut back on the food ie the alcohol - I feed about 25 mls of NEAT cheap supermarket vodka in 5 5ml doses throughout the day. But I have a flow rate of about 150 mls per minute on a 3000 lt system so you want to be about half of that.
I would bring it down in stages and allow a day between to see what it does to the redox.

This is assuming that you are sure that the central down pipe is not blocked as I first described.
You can see this is the case when the mesh goes black or green rather than white and you can also see that the water is not flowing in the small gap at the bottom of the mesh beneath the support

This will bring down the redox.

All the best
Stuart