nfrank

I just bought a gallon of Metricide 28 on ebay for $17.50 shipped. Clearly, an impulse purchase. Not sure what i will use it for ....since i already use pressurized CO2 and dont have much visible algae. Guess i can experiment and can always share with friends.

Now that i bought it, i need to find out what i purchased , and if i got the right stuff

I already figured from reading this thred that i wont use the NaNO3 activator which also includes a rust inhibitor. I guess that the surfactant (wetting agent) is going to be a very small amount and at the concentrations that we use, it can be ignored, right?

What is the significance of the "28?" Is this the shelf life of the open bottle of disinfectant with the activator... before it polymerizes?(i.e. changes its organic carbon structure). I am guessing that the potency as algicide can change after that time although it can still be effective as source of carbon.

What do you folks think about Metricide 28 and what are your recommendations for its use?

Thanks.

overboard

So far, so good. I had worked off of the assumption that Excel is probably 2.5%; I think that was a ways back in this thread. I am dosing the Cidex Plus (3.4%) at the same amounts as Excel; daily at 1 ml per 10 gallons of tank size (not capacity), three times that at water changes. Apparently I am really overdosing, yet all plants and fish are OK so far. My main problem is green thread or hair algae- it is gone from one tank, well controlled in two others. I started using it in two tanks that I didn't use Excel in before. I didn't notice any real change in nitrate consumption, so there may be no connection there after all.

nfrank- don't use the activator. I am cynical, but I would suspect that it is just an indicator for the test strips they sell also, so that the manufacturer puts the liability for replacing the solution on the user, and makes sure they sell a lot more. Doesn't aspirin cost $5.00 each in the hospital...? I used my Cidex Plus for three months, and it seemed to work better and better, no sign of degrading.

gdevil

Are you sure of this? because in medicine studies have demostrate that glutaraldehyde lose his effects whit the pass of the time and also that in alcalyne ph is less strong this, so is more a stabilizator than an activator...

Any way i'm not use in it either...

overboard

You are probably right, it is a stabilizer.. I just guess that Cidex is an effective algeacide and carbon source even after it has degraded as a safe disinfectant. I just finished a quart I got four months ago, and started a new bottle, and noticed no difference in the 10 gallon that still has hair algae... alas.

ErioLover

Im sorry but I don't quite follow. Are u saying that it is useless when adding the activator? Or are u saying that cidex has no effect on algae? I just bought a bottle but its too early to tell its effects. It doesn't seem like it does much on spirogyra but neither does excel.

Seattle_Aquarist

Hi overboard,

Just an FYI, Post #115 (page 12 of this thread) is where the Glut concentration in Excel is mentioned to be 1.5%. This was determined as a result of testing done in India. The assumption of a 2.5% concentration is almost 2X the actual.

overboard

Wow, so when I thought I was 50% over, I was more than 130% stronger than Excel. I haven't seen any harmful effects, though. Thanks for the info- that's a lot of reading to do.

ErioLover- Cidex works great without the activator. Like you said, the algae that I still have was resistant to Excel also. And we are saving a LOT of money. I didn't use the activator because I thought that anything that is added to make a test work would be too strong, like I would never put the chemicals in my water test kits in the tank. I honestly have no idea if that is logical, but I didn't want to add what I couldn't identify.

SKSuser

I'm confused. I tried to buy some Cidex tonight and the current MSDS sheet says that it contains phthalaldehyde. Are you using this? Its a similar compound, but not the same.

Here's what I'm looking at, since I have an allmed in my town.
http://www.allmed.net/catalog/item/1,838,839,3030,862


Also, Wavicide says it has glutaraldehyde in it, but it also mentions a surfactant, a mild fresh scent, and a rust inhibitor.... I've heard of its use in the aquarium before, but recently it seems like glutaraldehyde alternatives, and their information, is getting sparse.

Squawkbert

I'm not sure about Cidex... may be a rose by any other name type situation.

As to the surfactant/scent, this is generally provided in another (smaller) bottle - don't use it if you're using this stuff as an Excel replacement.

ShayF

Do you have any reference to this Indian test?