I took all of my rock out and scrubbed it clean with a tooth brush. Plus I took all of the stuff out of the sump and scrubbed it clean as well. Now this is what it looks like now. Alot better and I did some landscaping and now I have an island in the middle of my tank with a 1 powerhead facing the back and 1 facing the front of the tank. It creates a whirlpool effect. I like it and the clowns love it. I attached some pics of my new design and my sump after I cleaned it.
Make sure your PH stay high in the 8.4. Low PH will leach cal/phospate and other material from your rock and sand.
Since you clean this much and it still grow algae. Remember when the algae grow on the rock it will lower the PH on and around the area and release the require chemical from the rock so it can grow.
I recommend dosing ALK to raise PH. remember dying coraline aglae will also release phospate into the water and on the rock when the PH is low.
I just finished correcting my new client 150 gal tank after it was taken over by algae due to neglect for a year.
I now Check their top off RO/DI for output less 5 ppm. The top off RO/ID system out put was over 200 PPM. I replaced all filter components and now the out put is 2 PPM. I also added Hiatt filter system to the setup. It keep the PH at 8.4 +. Also did a total system clean like you did.
I do 20% water change every two months.
I also recommend my client full cleaning of gravel under the rocks every 12 months. The Hiatt system generate lot of fine particle where the bacteria change nitrate into gas and use phospate for their growth and they do shead some phospate but in non useable form that algae can not use, but leave in the system for long term like a year other bateria can break it down.
If you want to use the Hiatt system. Do not buy the stuff they call PH rock. It is just Calcite (White Soft Marble) Pure crystaline Calcium carbonate. You can get that stuff from your land scaping store for a fraction of the price.
Good system, but carefull what you buy from them.