I have some questions, and even though I apologize for the long explanation below, I find it necessary to allow you guys to get a grip of whats up in the tank, and then be able to give me your proper advice.
I have an 8 gal
sump/refugium for my 20 gal
reef tank. All water parameters read fine, I have a phosphate reactor in which i change the media(phosban) monthly that has been yielding 0 phosphates for months now. The main tank does build very little algae, I have to scrape lightly the front glass maybe once a week if so. My nitrates are usually low too, maybe ranging in the 0-5-10 ppm
depending how heavy I feed the bottled zooplancton/phytoplancton to my soft corals. I am usually good with the feeding overall and have only 4 small fish in the tank.I do top offs with distilled water(I tested the brand I usually buy, and it has no copper or phosphates), and WC
's every 2 weeks(10%) which I use Nutri-Seawater because the cost isnt bad for the tank size I have(I use one 4.4gal, $15 bottle/month)
I have 3x 13W power compact lights with 5000K and 6700K bulbs ON for about 12 hours/day on the refugium, while I run a 150W metal halide for 8 hours/day on the main one. In the Fuge, I have Caulerpa and Chaeto.
So, getting to the questions :
1- I have some thick reddish/bubbly algae on some of the walls of the fuge, with also some thick dark green ones on some of the macros(again, the algae I have issues are only in the refugium area, on the main tank I only have light brown film on glass occasionally). The growth of the macros have been ok, the Caulerpa has been growing really fast, rooting everywhere. Should not worry and let the nuisance algae grow in the sump area or should I clean the fuge glass, trying to remove it when I perform water changes in the tank? Should I throw in some turbo snails/other algae eaters in it to help keep it down, or that algae could be beneficial/compete with the ones from the main tank? I have moved a marble star fish from the main tank to the sump to let it have some fun with the algae, and by the way it is constantly moving in the sump, my thoughts are that it is finding some algae to graze on.
I do not like cleaning the glass of the sump because I find that it sort of disturbs the pods
on the glass, where is the spot I want them to hang and thrive. However, Im not sure if I should start to clean that algae...please let me know your thoughts.
2- I have a 300 gal
/hr pump returning the water back to the tank, which if my calculations are right, its pretty good flow for a 20 gal
I notice that the middle column of the sump water is moving because of that flow; but the fuge surface is not at all. I added today a little sub pump doing some agitation with a flow regulator on the surface to get the water moving just a bit. Would that non moving top water be contributing to the growth of the algae?
THanks guys, your comments are really appreciated and I will consider them for any changes that might take place in the tank!
I will try to post pics so you can see better, but maybe for now the description will be enough.
Have a good day