Freshwater DIY HOG UAS

[comet]

The Setup:
75 Gallon freshwater tank
EHIEM proE 700 canister filter
nitrates over 70ppm and mitigating this via 20% water changes weekly (basically vacuum the substrate)
2 x 3" goldfish
1/2 tbsp of pellet food each day
blue/white LED which is left on about 8h/day

Problem is that I have algae issues on all surfaces in the tank and water clarity issues from algae. I do not want to leave the tank dark ( I like to look at my fish ) to control the algae and I would like to lower my water bill and the amount of time I spend maintaining my tank.

Goldfish keepers LOVE to change water a lot and it seems that many control water quality only via water changes (and lots of them). That would be great if I had someone else paying the water/sewer bill and had the time to do it :). My search for a more manageable water change cycle pointed me towards algae scrubbers.

Present Day:
I have done a TON of reading and I have started to plan out how I am going to build my scrubber. My plan is to base my build off of santa monica's HOG UAS, so I got a free license from his site. Even though I don't plan to sell things, I want this to be legit and give credit where it is due. I would love to get any feedback (good or bad).

The plan is to use 2 - 4" x 6" x 2" ABS Black DIY boxes from the shack one one each side of the glass. I figured based on sizing for the amount I feed that about 20 sq inch single sided panel should work for now and if I get one or two more fish.

On the other side I will be using 6 - Solderless Philips Rebel ES 660nm Deep Red LED's. My theory behind this is that I can fit that many on there AND with the solderless, I can disconnect half of them during the first phase of initializing the scrubber so that the light is not as intense.

I have a few questions (for now :):
Is my LED quantity theory founded?
Is 6 LED's too much for the size of the scrubber once it is fully up and running?
I am going to need to drill holes for water flow. What are your suggestions for placement and size?

[Floyd R Turbo]

Is your display tank lighting very intense? If you don't have any plants, there's no reason for high intensity light. You just want enough light to make it viewable. Too much light and you get algae blooms.

Your LED array it good. I agree with your philosophy of half the LEDs at first. How do you intend to keep the boxes attached to each other, magnets? Suction cups?

Holes, I would just drill a bunch on the top and bottom so that they water draws up and through. Bring the airline in to the bottom and install a horizontal plate with holes drilled in it in the box above the air entry point, this will let the bubbles pool under it and the air will then distribute via the holes. Don't do the slotted airline or airstone thing, those both clog.

[SantaMonica]

Welcome.

6 of those LEDs is very strong, but if you start off with less then it might work. If you can coat all the insides of the container with texture, you will make use of more space.

Also, FW growth thinner, longer, straight algae. If you can choose any shape, make the scrubber taller and narrower so that the long growth will stay inside more before going out through the holes. Otherwise your fish will be eating endlessly :)

[comet]

For the display lighting I have an aquatic life 0.5 W LED strip of maybe 30 white and 30 blue (I can't remember the exact amount), but I don't think its over doing it.

I think I am going to use magnets as it will allow me to position the two sides together much easier (has anyone used kjmagnetics.com? or would recommend another dealer?).

I was thinking of drilled/slotted airline, but the plate idea is a much better one now that you mentioned it. I will have the holes drilled as close to the growing surface as possible to ensure contact. What diameter holes and how many for the air do you think would be best? 1/16? spaced 1/2" apart?

I will do some research into coating the inside with texture (I know I saw a number of threads here about how others have done it).

[Floyd R Turbo]

I've used http://www.gaussboys.com/ but really it's just price shopping. Remember that even in freshwater, you need to seal the magnets. Probably a little less important as freshwater is less corrosive, but neodymium magnets have many components that are toxic in aquaria so you need to seal them fully. Also when paired they do need to be aligned correctly or else they repel.

Holes, I suppose it's related to the amount of air. Also they will grow algae right at the holes and will close up between cleanings, I'd go with 1/8" and make lots of them in a grid pattern, maybe 3/8" on center.

[comet]

Sounds good! What do you recommend sealing and adhering the magnets with? I was thinking this: super-glue-waterproof-epoxy-adhesive (www.supergluecorp.com/super-glue/epoxies/waterproof-epoxy-adhesive)

[Floyd R Turbo]

Standard epoxy is fine. You don't need anything special that can cure underwater, in fact you want plain-jane epoxy - no additives. Once it dries is it not reactive with anything.

When you position the magnet, leave a little gap between where the magnet will be and where the glass is, maybe 1/16", and fill that in with epoxy as well (you can sand the epoxy down afterwards too if it's not perfectly flat). The point is no water contact

[SantaMonica]

Without a slotted airline, or a bubble divider, you are going to need more air to fill up that compartment.

[comet]

What would a bubble divider look like? Do I just want smaller bubbles?

[SantaMonica]

Look here
http://www.youtube.com/watch?v=3D1gHHxJlkA