Nano keeps crashing

[lizardlady]

I grow nano to feed my rotifers with limited success. I use new sea water with a ph of about 7.6-8.6 with a salinity of 1.014 and sterilize all my equipment with bleach being careful to neutralize bleach after the equipment is cleaned. I have also tried not bleaching with same results. My air pump is kept up high at the other end of the room. I start out with about 6 gallons of nano that I get from a friend (who has never had problems) which I put in a clean glass jug used for making wine. I add 1 gallon of prepared new water and fertilizer specifically used for phyto (f2). I find the nano crashes much faster if I add more then 1 quarter new water. I have tried under fertilizing and over fertilizing but each time without fail within two weeks the culture becomes pale and dies. I usually harvest every four to five days and replace and fertilize as needed. I have tried waiting the recommended one week but the nano starts to go pale around day 7. I have checked for rotifers which has been the cause of some crashes but this situation is rare. Temp is about 70-72. My rotifers and baby clowns seem perfectly fine and since I moved everything to the new fish room I have never had a rotifer crash (cross my fingers). I would really like to figure this out now that two more pairs have spawned and the need for more nano looms on the horizon. Any advice is much appreciated.

 

[lizardlady]

Update: I found out that my fertilizer had gone bad,, much fewer crashes since I replaced it but still cannot add more then one third new water, if I do, the nano crashes, anyone got any ideas? Oh yes, I use double 48" t-8s.

 

[lizardlady]

Got it figured out!

Got it figured out!

Finally figured out the problem! Turns out that whatever is contaminating my greenwater can't handle lower ph. I noticed that the greenwater for my batch cultures for rotifer gut loading seemed to do just fine. I realised that the only difference between the batch cultures and the normal cultures was a lower ph. I lowered the ph in my normal cultures to 6.5 and I have had no contamination since! Even one batch that I thought was beyond saving recovered! I am now trying to dilute batches to 1/2 to see if I can do better then 1/3 replacement water.

 

[vlangel]

Finally figured out the problem! Turns out that whatever is contaminating my greenwater can't handle lower ph. I noticed that the greenwater for my batch cultures for rotifer gut loading seemed to do just fine. I realised that the only difference between the batch cultures and the normal cultures was a lower ph. I lowered the ph in my normal cultures to 6.5 and I have had no contamination since! Even one batch that I thought was beyond saving recovered! I am now trying to dilute batches to 1/2 to see if I can do better then 1/3 replacement water.

Glad it worked out! I love a happy ending.:dance: