finally got scrubber up and running

It's not too bad, but since you're only feeding 1 cube/day I would go to this schedule:

4 on
1 off
4 on
15 off

 

The center is filling in nicely, but I would leave it at the schedule you have now for another cycle

 

I would give it a light rinse and rub with your fingertips. You will probably not get very much algae releasing from the screen, but you want to break loose any poorly attached growth

 

You could go to solid 9 hrs now that the center has filled in. You're looking about right for the 2-3 week point. You're starting to get some green so that's good. I would expect more growth over the next few weeks, every system is different.

You can probably rinse it and run lightly, not much should come off though. And that's ok.

 

Alsoif you want to get someone's attention (if they are not on the thread, for instance) you can tag users in a post and they will get an alert like this @Garf

 

Just scanned through the thread, here's a progression sequence

Day 1ish


Day 10



Day 13



Day 21



Day 28ish



You are on the right track, at this point you can probably give the screen a rub w/fingertips and rinse under tap water, nothing too aggressive.

After that, increase the flow a bit. I think after looking at the first vid again that your flow seemed a bit on the low side but that was OK because flow isn't a huge factor in the maturing stage. I would leave light hours at 9 still

How is your tank? Any changes? Any algae problems? Nitrate & Phosphate readings?

 

Yes, you can pick at the large clumps to thin them out a bit, or scrape them off with fingernails. There might be some firmly attached growth, you can leave that (survival of the fittest)

 

The bubbles are typically a result of oxygen production from photosynthesis, nothing to worry about.

The darker reddish patches could be the start of actual 'turf' algae, which is not bad, but generally GHA grows faster so that's what you want.

The center area of the screen looks like it's filling in better with GHA, it looks more even, so that's good.

I scanned the thread and I didn't see how much you are feeding, but 50g tank with a few small fish, so I'm guessing you're not feeding any more than 1 cube of food per day, does that sound about right?

Also, you last mentioned that your N and P were very low, so the scrubber is doing the job keeping those in check, and that is the purpose. Getting algae to grow thick and lush is not necessarily required for it to be doing the job - this is all dependent on the tank. The growth I get, and that you see a few others getting on here, is in tanks that are stocked/fed a little more heavily. So don't get too hung up on the type and amount of growth you are getting as long as the scrubber is keeping nutrients and tank algae in check. The fact is that scrubbers will grow algae in direct correlation to the tank conditions: amount fed, condition of water/rocks, and livestock type/load.

It would be OK to take a toothbrush or even the grout brush to the reddish growth areas along the edges of the screen, don't scrub really hard, but just enough to clean that area off. Then leave the center/green areas pretty much alone, maybe a swipe or two with the toothbrush and a quick rinse. You don't really need to scrape the screen when you can still see the underlying screen pattern under the GHA growth, because it's not thick enough to prevent light from penetrating.

If I made any incorrect assumptions here, please let me know

 

As long as you follow the old standby rule of feeding what they can eat in X minutes (was that 3 or 5?) then you're fine. Any additional food will decompose, get eaten by cleanup crew, etc, but may contribute to the diatoms.

If you haven't ran a scrubber on the tank before, then the system will go through a phase where things will change slightly. What these 'things' are, we really don't know, but probably something that changes the 'set point' of the system, and there are likely some chemical changes that occur a bit at a time. Like most things in the aquarium hobby, anecdotal evidence is all we have. Anytime to change something, be that a maintenance habit or adding or removing a piece of equipment, you change the 'set point'. What I've noticed based on my experience and some feedback is that occasionally making a change can cause some unintended effects, but they are usually temporary.

The #1 rule that you should generally follow is to only make one change at a time. So if you stopped making water changes after you added the scrubber, that's 2 changes. Then, you started dosing Alk, Cal, and Mag to make up for what you were doing with the now absent water changes - that's 3 changes. Or 5, depending on how you look at it. Now don't go doubling up on a water change to make up for it, but I would ease back into the water changes with one that is maybe 50% of what you were doing, then the next time do the normal water change. Or do 50% and dose less, but whatever you do, keep it consistent until the scrubber shows that it's producing regularly (that is, whatever it is producing, it is consistent) and your tank shows signs of stability - no algae outbreaks, nothing out of the ordinary, etc. Then, you can ease back on water changes that you were doing for the purposes of nutrient reduction.

But I would keep up on 10% every other week at a minimum, as this can relieve a lot of issues caused by chemical changes or chemical warfare. I had the opportunity to listen to Bob Fenner at our last fest and after hearing what he had to say about chemical interactions, I support maintaining some level of regular water changes. That is, unless you never want to add anything new to your tank...everything in it will generally 'get used to' the soup they are in.