BBA problem

[vidiots]

I have a 180g 24x24x72 planted tank, 4.3wpg, 6hr light period, pressurized CO2, DIY 20g sump mattenfilter. DIY Automatic water changer (~10%daily), DIY Auto Doser Dosing ~1/2 EI amounts daily instead of full amount every other day. My CO2 is disolved in the sump using a DIY power head diffuser. I have the CO2 on a timer that turns it off at night.

I thought I was doing good by keeping my CO2 1.0pH below the degassed level.
But I am having some problems with stubborn BBA growing mainly on the short plants in my tank like the microswords which are heavily covered and it grows back faster than I can remove it.

I saw a post where Tom mentioned water circulation as a possible cause. So I'm gonna try aiming the current my returns downward more towards the microswords. Just wondering if you had any other suggestions like, Do I have too long of a light period?

 

[VaughnH]

Re: BBA problem

I don't think your lighting period is anywhere near too long, but 4.3 watts per gallon for a 180 gallon tank??? That seems like extreme overkill to me. Half of that should be enough to grow almost anything. If it isn't just the massive overdose of light causing the BBA then I will bet it is a too low CO2 level in the tank water. Since those of us without unlimited funds to spend on this hobby can't really accurately measure CO2, and most of our measurements are going to be on the low side, I think the best way to handle CO2 is to raise the bubble rate a bit each day or two, carefully watching to see if the new BBA growths have stopped, and to see if the fish are affected. It should be possible to hit a bubble rate where no more new BBA growths start up, but the fish aren't distressed.

 

[vidiots]

Re: BBA problem

I don't think your lighting period is anywhere near too long, but 4.3 watts per gallon for a 180 gallon tank??? That seems like extreme overkill to me. Half of that should be enough to grow almost anything. If it isn't just the massive overdose of light causing the BBA then I will bet it is a too low CO2 level in the tank water. Since those of us without unlimited funds to spend on this hobby can't really accurately measure CO2, and most of our measurements are going to be on the low side, I think the best way to handle CO2 is to raise the bubble rate a bit each day or two, carefully watching to see if the new BBA growths have stopped, and to see if the fish are affected. It should be possible to hit a bubble rate where no more new BBA growths start up, but the fish aren't distressed.

My origional plan was to stagger the lighting thru the day, creating a sun rise sun set effect, but I had some difficulties with the all the expensive digital timers I bought for this, and haven't had the funds to get different ones yet. For now I have all the lights plugged into a powerstrip which is plugged into a single mechanical timer. I can kill a couple of them, until I get enough reliable timers to do as planned, if you think it will help. I can also try turning up the CO2 a bit more.

 

[Laith]

Re: BBA problem

My suggestion would be to get a second mechanical timer and split your lights between the two.

Then use the noon burst photoperiod; half the lights for an hour or two, all the lights for four or five hours and then half the lights again for an hour or two...

 

[vidiots]

Re: BBA problem

Thanks for the suggestion. I'll try that too.

I also discovered another possible cause. Since the EI example doses were not available for larger tanks I had to make a spread sheet to calculate the doses for my ferts. I used it to calculate my doses and initially saw some pearling and all was well. A while back someone else needed help calculating their doses so I plugged their tank size into my spreadsheet (which was half the size of my tank). I must have accidently saved it. For the last few months I've been refering back to my spreadsheet when mixing up the fert solutions and not paying attention to the fact that the tank size was wrong in the spreadsheet and as a result was only dosing 1/2 the amount I should and thinking I was dosing the proper EI amount. I hadn't been seening the expected amount of pearling lately, and think I neglected to mention that in my first post.

Wasn't until today when I was considering tweaking the amounts to try to improve things. In rereading the EI articles I noticed my amounts were off and traced it back to my calculator which was calculating correctly but for the wrong tank size. OOOps.

 

[Tom Barr]

Re: BBA problem

10 hours low light, 3 hours full light.
Cheapy timers work fine.

Bump up the CO2.
By the time the CO2 is cranking good and well mixed in the tank, the low lights have been on for say 3 hours, then you blast all the lights for 3-4 hours more, then 3-4 hours of low lights again after havign sucked a lot of the CO2 out of the water.

This has a similar effect to the siesta, although reversed and a better method, gives the CO2 system time to build up enough CO2 in the water to make sure the light driven CO2 demand is met.

EI and automatic water changes tend to work best when you do 2x a week 40-80% water changes rathwer than small daily water changes.
If you do water changes, do large ones and frequent.

10% is not much dilution factor vs 50%.

I think that, and lighting, and CO2 tweaking will greatly improve things for you.


Regards,
Tom Barr