how often should I add a drop or 2 of biocide in my loop?

[newls1]

I just finished up my new loop 2 days ago, and am only using distilled water and 4 drops of biocide in my loop (I have about 3/4 gallon of capacity of h20 in my loop) should I be adding a drop or 2 every month or so??? Im so sick and tired of stained tubes, and colored dyes, etc... so I chose just water this time around:up: Thanks

[Soulwind]

It depends on WHAT biocide you're using.

As I understand it, some kinds of biocide (like the stuff for fish-tanks) break down over time and need to be refreshed periodically.

Other kinds, like the stuff that's toxic to all life, tends to last indefinately.

(at least that's been my experience so far...I went nearly a year without adding more PT Nuke to my loop. I added the correct amount of it to the gallon jug of distilled when first opened and just used the rest of the gallon when topping off the loop)

[brammers]

I put 2 drops of PT Nuke (not the PHN version) per litre (which is about 7-8 drops per US gallon) and I add another 2 drops every 6 months (which I shouldn't really need to I expect).

My loop holds about 1.8 litres - so approx 1/2 US gallon.

My top-up water is the leftover from the second 1 litre bottle which has the Nuke already in it.

I've never had a problem with buildup of any kind (except the usual Tygon leech) and I left the loop for 18 months last time.

HTH
J

[zanzabar]

if u have the blue pt nuke its a 1 time deal as copper sulfate should not degrade and should last a minimum of 1.5-2 years (when u should clean the loop out)

[brammers]

Thanks, I'll keep that in mind.

J

[penguins]

You link a thread called "When you don't use biocide"

Or is your only concern his copper res? makes no sense to link that thread.

[Rubycon]

It depends on WHAT biocide you're using.

As I understand it, some kinds of biocide (like the stuff for fish-tanks) break down over time and need to be refreshed periodically.

Other kinds, like the stuff that's toxic to all life, tends to last indefinately.

(at least that's been my experience so far...I went nearly a year without adding more PT Nuke to my loop. I added the correct amount of it to the gallon jug of distilled when first opened and just used the rest of the gallon when topping off the loop)

The stuff added to fish tanks is the OPPOSITE of biocide! It actually contains seeds for beneficial bacteria essential for the proliferation of the infamous nitrogen cycle which is essential for all marine life forms to thrive in a captive environment.

In cooling systems you want to keep microbe count as low as possible. Even if tubing is opaque and everything else is relatively dark, slimes can still form which you don't want.

If that's not enough, dissolved gases - particularly oxygen - are bad and should be scavenged as soon as possible when circulation begins. This is why it's essential to have a blend of treatments - corrosion inhibitors, germicidal agents, and oxygen scavengers - to quickly balance your coolant and keep cycles of concentration where they should be. The bad news is this requires extensive testing and monitoring to make sure it's perfect. In small PC systems this is frustrating to say the least because trial and error is a pain in the hindpart - but still inexpensive compared to complex cooling plants commonly seen in industry, etc.

The experience and knowledge the average hobbyist gains can be useful and fun though, right? :ROTF:

[rge]

I wouldnt add any more biocide if you used PT nuke copper sulfate, and definitely not every month. And probably not even if used PHN (benzalkonium chloride).

If you used PT nuke, then you added ~ .8 ppm of copper sulfate which is enough, and in time, the copper concentration will increase not decrease as more copper is leached from your blocks. There is a governmental study in previous thread that gives the concentration over time from some copper pipe exposure in closed loop to distilled water, but in months you will likely be in 1-2+ ppm.

My current loop of distilled/PT nuke has been up for 13 months (isnt longest by any means), and water, tubes, res all crystal clear, and like in past, it will not be changed until I upgrade something, likely in 1st qrtr 2012. When I do top it off about every 6 months with inch or 2 in res, I add same .8 ppm copper sulfate gallon of distilled I had mixed a year ago.