Fluval Cycle and other bacteria questions for brackish

Tain't fresh, and tain't marine! Talk about brackish setups.
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Fluval Cycle and other bacteria questions for brackish

Post by cds333 » Mon Oct 01, 2018 3:07 pm

I have heard some conflicting things about which bacteria to use and when.

I hear a lot of people saying to use biospira and also some say to use Fluval Cycle.

I have also read that changing the salinity more than .002 at once will kill off the BB, however according to Fluval with whom I just spoke on the phone, the Cycle product does not contain both freshwater and marine bacteria, but instead a bacteria that works for both. This sounds fishy. The sheet for Cycle is useless of course, as it does not list any bacteria strains.

Another post I read says that freshwater biospira bacteria is good up to 1.008

-So what strains of bacteria will be killed if you transition more than .002 at once? How slowly must you do this for them to catch up without dying? Does anyone have any official evidence of this or is it all just pseudoscience?

-Which type of bacteria is the one to use for a tank that is currently between 1.003-1.005 salinity?

-How long does Fluval Cycle take to cycle a tank when using the recommended dosage?

-What could be the cause for a tank getting stuck at 0.25/0/<=10 and not transitioning to 0/0/<=10 ?

My f8 puffer is acting funny (lethargic, swimming at odd angles, bumping into things, not hungry) and I would imagine that this is due to the very low levels of ammonia still present, although the tank was established with an entire HOB filter from a same-gallon FW tank, and also treated with Cycle, so idk why this should be happening. I have started tanks this way before with no issues. The color of the ammonia test is right at 0.25 for the FW card and 0.0 for SW card. So the actual level is somewhere between 0 and 0.25. He was fine for 3 weeks until two days ago when he started acting weird and ignoring his tankmate (gsp, who is fine)


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Re: Fluval Cycle and other bacteria questions for brackish

Post by Pufferpunk » Mon Oct 01, 2018 10:44 pm

Cycle is total CRAP! Nothing but DEAD bacteria in a bottle. Bio-Spira is only for SW & Dr Tim's or Tetra Safestart is for FW. I wouldn't recommend anything else.
Of course, these products are only for emergency cycling. Fishless Cycling is always the best route to go.

Bumping into things is a symptom of nitrite poisoning. Start doing 80% WC, to keep the toxic ammonia/nitrite at 0. Add Prime to detoxify those chemicals. Add Safestart or Dr Tim's directly to your filter, ASAP.

Keep the tank FW until the parameters are stable for at least a month. Then you can slowly transition the bacteria to BW.
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Re: Fluval Cycle and other bacteria questions for brackish

Post by Iliveinazoo » Tue Oct 02, 2018 5:26 pm

The cause for the tank sticking at 0.25ppm ammonia could be that it takes around 4-6 weeks to cycle when doing a fishless cycle so it stands to reason that an overstocked tank would take longer. The fact that the tank is overstocked could also be the problem because you could be exceeding the capacity of the filter.

I would use FW bacteria at SG1.003.

The reason that people say don’t change salinity by more than 0.002 a week is to play it safe, some bacteria will die off but not enough to cause a system crash but the more you change then the greater the risk. There was a knowledgeable person called RTR that used to post on here that said that greater changes between SG1.000 and SG1.008 probably wouldn’t hurt so much as changes between Sg1.008 and SG1.015 because of the transition betwen freshwater nitrifying bacteria and salt water nitrifying bacteria. If you stick to the well versed rule then you won’t go far wrong. :D

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